//
// TODO: Handle multiple loops at a time.
//
-// TODO: Should TargetLowering::AddrMode::BaseGV be changed to a ConstantExpr
-// instead of a GlobalValue?
+// TODO: Should the addressing mode BaseGV be changed to a ConstantExpr instead
+// of a GlobalValue?
//
// TODO: When truncation is free, truncate ICmp users' operands to make it a
// smaller encoding (on x86 at least).
//
//===----------------------------------------------------------------------===//
-#define DEBUG_TYPE "loop-reduce"
#include "llvm/Transforms/Scalar.h"
-#include "llvm/Constants.h"
-#include "llvm/Instructions.h"
-#include "llvm/IntrinsicInst.h"
-#include "llvm/DerivedTypes.h"
+#include "llvm/ADT/DenseSet.h"
+#include "llvm/ADT/Hashing.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/SetVector.h"
+#include "llvm/ADT/SmallBitVector.h"
#include "llvm/Analysis/IVUsers.h"
-#include "llvm/Analysis/Dominators.h"
#include "llvm/Analysis/LoopPass.h"
#include "llvm/Analysis/ScalarEvolutionExpander.h"
-#include "llvm/Assembly/Writer.h"
-#include "llvm/Transforms/Utils/BasicBlockUtils.h"
-#include "llvm/Transforms/Utils/Local.h"
-#include "llvm/ADT/SmallBitVector.h"
-#include "llvm/ADT/SetVector.h"
-#include "llvm/ADT/DenseSet.h"
-#include "llvm/Support/Debug.h"
+#include "llvm/Analysis/TargetTransformInfo.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/Dominators.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/IntrinsicInst.h"
+#include "llvm/IR/ValueHandle.h"
#include "llvm/Support/CommandLine.h"
-#include "llvm/Support/ValueHandle.h"
+#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
-#include "llvm/Target/TargetLowering.h"
+#include "llvm/Transforms/Utils/BasicBlockUtils.h"
+#include "llvm/Transforms/Utils/Local.h"
#include <algorithm>
using namespace llvm;
+#define DEBUG_TYPE "loop-reduce"
+
/// MaxIVUsers is an arbitrary threshold that provides an early opportunitiy for
/// bail out. This threshold is far beyond the number of users that LSR can
/// conceivably solve, so it should not affect generated code, but catches the
OS << "[NumUses=" << UsedByIndices.count() << ']';
}
+#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
void RegSortData::dump() const {
print(errs()); errs() << '\n';
}
+#endif
namespace {
/// computing satisfying a use. It may include broken-out immediates and scaled
/// registers.
struct Formula {
- /// AM - This is used to represent complex addressing, as well as other kinds
- /// of interesting uses.
- TargetLowering::AddrMode AM;
+ /// Global base address used for complex addressing.
+ GlobalValue *BaseGV;
+
+ /// Base offset for complex addressing.
+ int64_t BaseOffset;
+
+ /// Whether any complex addressing has a base register.
+ bool HasBaseReg;
+
+ /// The scale of any complex addressing.
+ int64_t Scale;
/// BaseRegs - The list of "base" registers for this use. When this is
- /// non-empty, AM.HasBaseReg should be set to true.
- SmallVector<const SCEV *, 2> BaseRegs;
+ /// non-empty. The canonical representation of a formula is
+ /// 1. BaseRegs.size > 1 implies ScaledReg != NULL and
+ /// 2. ScaledReg != NULL implies Scale != 1 || !BaseRegs.empty().
+ /// #1 enforces that the scaled register is always used when at least two
+ /// registers are needed by the formula: e.g., reg1 + reg2 is reg1 + 1 * reg2.
+ /// #2 enforces that 1 * reg is reg.
+ /// This invariant can be temporarly broken while building a formula.
+ /// However, every formula inserted into the LSRInstance must be in canonical
+ /// form.
+ SmallVector<const SCEV *, 4> BaseRegs;
/// ScaledReg - The 'scaled' register for this use. This should be non-null
- /// when AM.Scale is not zero.
+ /// when Scale is not zero.
const SCEV *ScaledReg;
/// UnfoldedOffset - An additional constant offset which added near the
/// live in an add immediate field rather than a register.
int64_t UnfoldedOffset;
- Formula() : ScaledReg(0), UnfoldedOffset(0) {}
+ Formula()
+ : BaseGV(nullptr), BaseOffset(0), HasBaseReg(false), Scale(0),
+ ScaledReg(nullptr), UnfoldedOffset(0) {}
void InitialMatch(const SCEV *S, Loop *L, ScalarEvolution &SE);
- unsigned getNumRegs() const;
+ bool isCanonical() const;
+
+ void Canonicalize();
+
+ bool Unscale();
+
+ size_t getNumRegs() const;
Type *getType() const;
void DeleteBaseReg(const SCEV *&S);
const SCEV *Sum = SE.getAddExpr(Good);
if (!Sum->isZero())
BaseRegs.push_back(Sum);
- AM.HasBaseReg = true;
+ HasBaseReg = true;
}
if (!Bad.empty()) {
const SCEV *Sum = SE.getAddExpr(Bad);
if (!Sum->isZero())
BaseRegs.push_back(Sum);
- AM.HasBaseReg = true;
+ HasBaseReg = true;
}
+ Canonicalize();
+}
+
+/// \brief Check whether or not this formula statisfies the canonical
+/// representation.
+/// \see Formula::BaseRegs.
+bool Formula::isCanonical() const {
+ if (ScaledReg)
+ return Scale != 1 || !BaseRegs.empty();
+ return BaseRegs.size() <= 1;
+}
+
+/// \brief Helper method to morph a formula into its canonical representation.
+/// \see Formula::BaseRegs.
+/// Every formula having more than one base register, must use the ScaledReg
+/// field. Otherwise, we would have to do special cases everywhere in LSR
+/// to treat reg1 + reg2 + ... the same way as reg1 + 1*reg2 + ...
+/// On the other hand, 1*reg should be canonicalized into reg.
+void Formula::Canonicalize() {
+ if (isCanonical())
+ return;
+ // So far we did not need this case. This is easy to implement but it is
+ // useless to maintain dead code. Beside it could hurt compile time.
+ assert(!BaseRegs.empty() && "1*reg => reg, should not be needed.");
+ // Keep the invariant sum in BaseRegs and one of the variant sum in ScaledReg.
+ ScaledReg = BaseRegs.back();
+ BaseRegs.pop_back();
+ Scale = 1;
+ size_t BaseRegsSize = BaseRegs.size();
+ size_t Try = 0;
+ // If ScaledReg is an invariant, try to find a variant expression.
+ while (Try < BaseRegsSize && !isa<SCEVAddRecExpr>(ScaledReg))
+ std::swap(ScaledReg, BaseRegs[Try++]);
+}
+
+/// \brief Get rid of the scale in the formula.
+/// In other words, this method morphes reg1 + 1*reg2 into reg1 + reg2.
+/// \return true if it was possible to get rid of the scale, false otherwise.
+/// \note After this operation the formula may not be in the canonical form.
+bool Formula::Unscale() {
+ if (Scale != 1)
+ return false;
+ Scale = 0;
+ BaseRegs.push_back(ScaledReg);
+ ScaledReg = nullptr;
+ return true;
}
/// getNumRegs - Return the total number of register operands used by this
/// formula. This does not include register uses implied by non-constant
/// addrec strides.
-unsigned Formula::getNumRegs() const {
+size_t Formula::getNumRegs() const {
return !!ScaledReg + BaseRegs.size();
}
Type *Formula::getType() const {
return !BaseRegs.empty() ? BaseRegs.front()->getType() :
ScaledReg ? ScaledReg->getType() :
- AM.BaseGV ? AM.BaseGV->getType() :
- 0;
+ BaseGV ? BaseGV->getType() :
+ nullptr;
}
/// DeleteBaseReg - Delete the given base reg from the BaseRegs list.
void Formula::print(raw_ostream &OS) const {
bool First = true;
- if (AM.BaseGV) {
+ if (BaseGV) {
if (!First) OS << " + "; else First = false;
- WriteAsOperand(OS, AM.BaseGV, /*PrintType=*/false);
+ BaseGV->printAsOperand(OS, /*PrintType=*/false);
}
- if (AM.BaseOffs != 0) {
+ if (BaseOffset != 0) {
if (!First) OS << " + "; else First = false;
- OS << AM.BaseOffs;
+ OS << BaseOffset;
}
for (SmallVectorImpl<const SCEV *>::const_iterator I = BaseRegs.begin(),
E = BaseRegs.end(); I != E; ++I) {
if (!First) OS << " + "; else First = false;
OS << "reg(" << **I << ')';
}
- if (AM.HasBaseReg && BaseRegs.empty()) {
+ if (HasBaseReg && BaseRegs.empty()) {
if (!First) OS << " + "; else First = false;
OS << "**error: HasBaseReg**";
- } else if (!AM.HasBaseReg && !BaseRegs.empty()) {
+ } else if (!HasBaseReg && !BaseRegs.empty()) {
if (!First) OS << " + "; else First = false;
OS << "**error: !HasBaseReg**";
}
- if (AM.Scale != 0) {
+ if (Scale != 0) {
if (!First) OS << " + "; else First = false;
- OS << AM.Scale << "*reg(";
+ OS << Scale << "*reg(";
if (ScaledReg)
OS << *ScaledReg;
else
OS << ')';
}
if (UnfoldedOffset != 0) {
- if (!First) OS << " + "; else First = false;
+ if (!First) OS << " + ";
OS << "imm(" << UnfoldedOffset << ')';
}
}
+#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
void Formula::dump() const {
print(errs()); errs() << '\n';
}
+#endif
/// isAddRecSExtable - Return true if the given addrec can be sign-extended
/// without changing its value.
// Check for a division of a constant by a constant.
if (const SCEVConstant *C = dyn_cast<SCEVConstant>(LHS)) {
if (!RC)
- return 0;
+ return nullptr;
const APInt &LA = C->getValue()->getValue();
const APInt &RA = RC->getValue()->getValue();
if (LA.srem(RA) != 0)
- return 0;
+ return nullptr;
return SE.getConstant(LA.sdiv(RA));
}
if (IgnoreSignificantBits || isAddRecSExtable(AR, SE)) {
const SCEV *Step = getExactSDiv(AR->getStepRecurrence(SE), RHS, SE,
IgnoreSignificantBits);
- if (!Step) return 0;
+ if (!Step) return nullptr;
const SCEV *Start = getExactSDiv(AR->getStart(), RHS, SE,
IgnoreSignificantBits);
- if (!Start) return 0;
+ if (!Start) return nullptr;
// FlagNW is independent of the start value, step direction, and is
// preserved with smaller magnitude steps.
// FIXME: AR->getNoWrapFlags(SCEV::FlagNW)
return SE.getAddRecExpr(Start, Step, AR->getLoop(), SCEV::FlagAnyWrap);
}
- return 0;
+ return nullptr;
}
// Distribute the sdiv over add operands, if the add doesn't overflow.
I != E; ++I) {
const SCEV *Op = getExactSDiv(*I, RHS, SE,
IgnoreSignificantBits);
- if (!Op) return 0;
+ if (!Op) return nullptr;
Ops.push_back(Op);
}
return SE.getAddExpr(Ops);
}
- return 0;
+ return nullptr;
}
// Check for a multiply operand that we can pull RHS out of.
}
Ops.push_back(S);
}
- return Found ? SE.getMulExpr(Ops) : 0;
+ return Found ? SE.getMulExpr(Ops) : nullptr;
}
- return 0;
+ return nullptr;
}
// Otherwise we don't know.
- return 0;
+ return nullptr;
}
/// ExtractImmediate - If S involves the addition of a constant integer value,
SCEV::FlagAnyWrap);
return Result;
}
- return 0;
+ return nullptr;
}
/// isAddressUse - Returns true if the specified instruction is using the
/// TODO: Allow UDivExpr if we can find an existing IV increment that is an
/// obvious multiple of the UDivExpr.
static bool isHighCostExpansion(const SCEV *S,
- SmallPtrSet<const SCEV*, 8> &Processed,
+ SmallPtrSetImpl<const SCEV*> &Processed,
ScalarEvolution &SE) {
// Zero/One operand expressions
switch (S->getSCEVType()) {
// multiplication already generates this expression.
if (const SCEVUnknown *U = dyn_cast<SCEVUnknown>(Mul->getOperand(1))) {
Value *UVal = U->getValue();
- for (Value::use_iterator UI = UVal->use_begin(), UE = UVal->use_end();
- UI != UE; ++UI) {
+ for (User *UR : UVal->users()) {
// If U is a constant, it may be used by a ConstantExpr.
- Instruction *User = dyn_cast<Instruction>(*UI);
- if (User && User->getOpcode() == Instruction::Mul
- && SE.isSCEVable(User->getType())) {
- return SE.getSCEV(User) == Mul;
+ Instruction *UI = dyn_cast<Instruction>(UR);
+ if (UI && UI->getOpcode() == Instruction::Mul &&
+ SE.isSCEVable(UI->getType())) {
+ return SE.getSCEV(UI) == Mul;
}
}
}
bool Changed = false;
while (!DeadInsts.empty()) {
- Instruction *I = dyn_cast_or_null<Instruction>(&*DeadInsts.pop_back_val());
+ Value *V = DeadInsts.pop_back_val();
+ Instruction *I = dyn_cast_or_null<Instruction>(V);
- if (I == 0 || !isInstructionTriviallyDead(I))
+ if (!I || !isInstructionTriviallyDead(I))
continue;
for (User::op_iterator OI = I->op_begin(), E = I->op_end(); OI != E; ++OI)
if (Instruction *U = dyn_cast<Instruction>(*OI)) {
- *OI = 0;
+ *OI = nullptr;
if (U->use_empty())
DeadInsts.push_back(U);
}
return Changed;
}
+namespace {
+class LSRUse;
+}
+
+/// \brief Check if the addressing mode defined by \p F is completely
+/// folded in \p LU at isel time.
+/// This includes address-mode folding and special icmp tricks.
+/// This function returns true if \p LU can accommodate what \p F
+/// defines and up to 1 base + 1 scaled + offset.
+/// In other words, if \p F has several base registers, this function may
+/// still return true. Therefore, users still need to account for
+/// additional base registers and/or unfolded offsets to derive an
+/// accurate cost model.
+static bool isAMCompletelyFolded(const TargetTransformInfo &TTI,
+ const LSRUse &LU, const Formula &F);
+// Get the cost of the scaling factor used in F for LU.
+static unsigned getScalingFactorCost(const TargetTransformInfo &TTI,
+ const LSRUse &LU, const Formula &F);
+
namespace {
/// Cost - This class is used to measure and compare candidate formulae.
unsigned NumBaseAdds;
unsigned ImmCost;
unsigned SetupCost;
+ unsigned ScaleCost;
public:
Cost()
: NumRegs(0), AddRecCost(0), NumIVMuls(0), NumBaseAdds(0), ImmCost(0),
- SetupCost(0) {}
+ SetupCost(0), ScaleCost(0) {}
bool operator<(const Cost &Other) const;
- void Loose();
+ void Lose();
#ifndef NDEBUG
// Once any of the metrics loses, they must all remain losers.
bool isValid() {
return ((NumRegs | AddRecCost | NumIVMuls | NumBaseAdds
- | ImmCost | SetupCost) != ~0u)
+ | ImmCost | SetupCost | ScaleCost) != ~0u)
|| ((NumRegs & AddRecCost & NumIVMuls & NumBaseAdds
- & ImmCost & SetupCost) == ~0u);
+ & ImmCost & SetupCost & ScaleCost) == ~0u);
}
#endif
return NumRegs == ~0u;
}
- void RateFormula(const Formula &F,
- SmallPtrSet<const SCEV *, 16> &Regs,
+ void RateFormula(const TargetTransformInfo &TTI,
+ const Formula &F,
+ SmallPtrSetImpl<const SCEV *> &Regs,
const DenseSet<const SCEV *> &VisitedRegs,
const Loop *L,
const SmallVectorImpl<int64_t> &Offsets,
ScalarEvolution &SE, DominatorTree &DT,
- SmallPtrSet<const SCEV *, 16> *LoserRegs = 0);
+ const LSRUse &LU,
+ SmallPtrSetImpl<const SCEV *> *LoserRegs = nullptr);
void print(raw_ostream &OS) const;
void dump() const;
private:
void RateRegister(const SCEV *Reg,
- SmallPtrSet<const SCEV *, 16> &Regs,
+ SmallPtrSetImpl<const SCEV *> &Regs,
const Loop *L,
ScalarEvolution &SE, DominatorTree &DT);
void RatePrimaryRegister(const SCEV *Reg,
- SmallPtrSet<const SCEV *, 16> &Regs,
+ SmallPtrSetImpl<const SCEV *> &Regs,
const Loop *L,
ScalarEvolution &SE, DominatorTree &DT,
- SmallPtrSet<const SCEV *, 16> *LoserRegs);
+ SmallPtrSetImpl<const SCEV *> *LoserRegs);
};
}
/// RateRegister - Tally up interesting quantities from the given register.
void Cost::RateRegister(const SCEV *Reg,
- SmallPtrSet<const SCEV *, 16> &Regs,
+ SmallPtrSetImpl<const SCEV *> &Regs,
const Loop *L,
ScalarEvolution &SE, DominatorTree &DT) {
if (const SCEVAddRecExpr *AR = dyn_cast<SCEVAddRecExpr>(Reg)) {
return;
// Otherwise, do not consider this formula at all.
- Loose();
+ Lose();
return;
}
AddRecCost += 1; /// TODO: This should be a function of the stride.
/// before, rate it. Optional LoserRegs provides a way to declare any formula
/// that refers to one of those regs an instant loser.
void Cost::RatePrimaryRegister(const SCEV *Reg,
- SmallPtrSet<const SCEV *, 16> &Regs,
+ SmallPtrSetImpl<const SCEV *> &Regs,
const Loop *L,
ScalarEvolution &SE, DominatorTree &DT,
- SmallPtrSet<const SCEV *, 16> *LoserRegs) {
+ SmallPtrSetImpl<const SCEV *> *LoserRegs) {
if (LoserRegs && LoserRegs->count(Reg)) {
- Loose();
+ Lose();
return;
}
if (Regs.insert(Reg)) {
RateRegister(Reg, Regs, L, SE, DT);
- if (isLoser())
+ if (LoserRegs && isLoser())
LoserRegs->insert(Reg);
}
}
-void Cost::RateFormula(const Formula &F,
- SmallPtrSet<const SCEV *, 16> &Regs,
+void Cost::RateFormula(const TargetTransformInfo &TTI,
+ const Formula &F,
+ SmallPtrSetImpl<const SCEV *> &Regs,
const DenseSet<const SCEV *> &VisitedRegs,
const Loop *L,
const SmallVectorImpl<int64_t> &Offsets,
ScalarEvolution &SE, DominatorTree &DT,
- SmallPtrSet<const SCEV *, 16> *LoserRegs) {
+ const LSRUse &LU,
+ SmallPtrSetImpl<const SCEV *> *LoserRegs) {
+ assert(F.isCanonical() && "Cost is accurate only for canonical formula");
// Tally up the registers.
if (const SCEV *ScaledReg = F.ScaledReg) {
if (VisitedRegs.count(ScaledReg)) {
- Loose();
+ Lose();
return;
}
RatePrimaryRegister(ScaledReg, Regs, L, SE, DT, LoserRegs);
E = F.BaseRegs.end(); I != E; ++I) {
const SCEV *BaseReg = *I;
if (VisitedRegs.count(BaseReg)) {
- Loose();
+ Lose();
return;
}
RatePrimaryRegister(BaseReg, Regs, L, SE, DT, LoserRegs);
}
// Determine how many (unfolded) adds we'll need inside the loop.
- size_t NumBaseParts = F.BaseRegs.size() + (F.UnfoldedOffset != 0);
+ size_t NumBaseParts = F.getNumRegs();
if (NumBaseParts > 1)
- NumBaseAdds += NumBaseParts - 1;
+ // Do not count the base and a possible second register if the target
+ // allows to fold 2 registers.
+ NumBaseAdds +=
+ NumBaseParts - (1 + (F.Scale && isAMCompletelyFolded(TTI, LU, F)));
+ NumBaseAdds += (F.UnfoldedOffset != 0);
+
+ // Accumulate non-free scaling amounts.
+ ScaleCost += getScalingFactorCost(TTI, LU, F);
// Tally up the non-zero immediates.
for (SmallVectorImpl<int64_t>::const_iterator I = Offsets.begin(),
E = Offsets.end(); I != E; ++I) {
- int64_t Offset = (uint64_t)*I + F.AM.BaseOffs;
- if (F.AM.BaseGV)
+ int64_t Offset = (uint64_t)*I + F.BaseOffset;
+ if (F.BaseGV)
ImmCost += 64; // Handle symbolic values conservatively.
// TODO: This should probably be the pointer size.
else if (Offset != 0)
assert(isValid() && "invalid cost");
}
-/// Loose - Set this cost to a losing value.
-void Cost::Loose() {
+/// Lose - Set this cost to a losing value.
+void Cost::Lose() {
NumRegs = ~0u;
AddRecCost = ~0u;
NumIVMuls = ~0u;
NumBaseAdds = ~0u;
ImmCost = ~0u;
SetupCost = ~0u;
+ ScaleCost = ~0u;
}
/// operator< - Choose the lower cost.
bool Cost::operator<(const Cost &Other) const {
- if (NumRegs != Other.NumRegs)
- return NumRegs < Other.NumRegs;
- if (AddRecCost != Other.AddRecCost)
- return AddRecCost < Other.AddRecCost;
- if (NumIVMuls != Other.NumIVMuls)
- return NumIVMuls < Other.NumIVMuls;
- if (NumBaseAdds != Other.NumBaseAdds)
- return NumBaseAdds < Other.NumBaseAdds;
- if (ImmCost != Other.ImmCost)
- return ImmCost < Other.ImmCost;
- if (SetupCost != Other.SetupCost)
- return SetupCost < Other.SetupCost;
- return false;
+ return std::tie(NumRegs, AddRecCost, NumIVMuls, NumBaseAdds, ScaleCost,
+ ImmCost, SetupCost) <
+ std::tie(Other.NumRegs, Other.AddRecCost, Other.NumIVMuls,
+ Other.NumBaseAdds, Other.ScaleCost, Other.ImmCost,
+ Other.SetupCost);
}
void Cost::print(raw_ostream &OS) const {
if (NumBaseAdds != 0)
OS << ", plus " << NumBaseAdds << " base add"
<< (NumBaseAdds == 1 ? "" : "s");
+ if (ScaleCost != 0)
+ OS << ", plus " << ScaleCost << " scale cost";
if (ImmCost != 0)
OS << ", plus " << ImmCost << " imm cost";
if (SetupCost != 0)
OS << ", plus " << SetupCost << " setup cost";
}
+#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
void Cost::dump() const {
print(errs()); errs() << '\n';
}
+#endif
namespace {
}
LSRFixup::LSRFixup()
- : UserInst(0), OperandValToReplace(0), LUIdx(~size_t(0)), Offset(0) {}
+ : UserInst(nullptr), OperandValToReplace(nullptr), LUIdx(~size_t(0)),
+ Offset(0) {}
/// isUseFullyOutsideLoop - Test whether this fixup always uses its
/// value outside of the given loop.
// Store is common and interesting enough to be worth special-casing.
if (StoreInst *Store = dyn_cast<StoreInst>(UserInst)) {
OS << "store ";
- WriteAsOperand(OS, Store->getOperand(0), /*PrintType=*/false);
+ Store->getOperand(0)->printAsOperand(OS, /*PrintType=*/false);
} else if (UserInst->getType()->isVoidTy())
OS << UserInst->getOpcodeName();
else
- WriteAsOperand(OS, UserInst, /*PrintType=*/false);
+ UserInst->printAsOperand(OS, /*PrintType=*/false);
OS << ", OperandValToReplace=";
- WriteAsOperand(OS, OperandValToReplace, /*PrintType=*/false);
+ OperandValToReplace->printAsOperand(OS, /*PrintType=*/false);
for (PostIncLoopSet::const_iterator I = PostIncLoops.begin(),
E = PostIncLoops.end(); I != E; ++I) {
OS << ", PostIncLoop=";
- WriteAsOperand(OS, (*I)->getHeader(), /*PrintType=*/false);
+ (*I)->getHeader()->printAsOperand(OS, /*PrintType=*/false);
}
if (LUIdx != ~size_t(0))
OS << ", Offset=" << Offset;
}
+#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
void LSRFixup::dump() const {
print(errs()); errs() << '\n';
}
+#endif
namespace {
/// UniquifierDenseMapInfo - A DenseMapInfo implementation for holding
/// DenseMaps and DenseSets of sorted SmallVectors of const SCEV*.
struct UniquifierDenseMapInfo {
- static SmallVector<const SCEV *, 2> getEmptyKey() {
- SmallVector<const SCEV *, 2> V;
+ static SmallVector<const SCEV *, 4> getEmptyKey() {
+ SmallVector<const SCEV *, 4> V;
V.push_back(reinterpret_cast<const SCEV *>(-1));
return V;
}
- static SmallVector<const SCEV *, 2> getTombstoneKey() {
- SmallVector<const SCEV *, 2> V;
+ static SmallVector<const SCEV *, 4> getTombstoneKey() {
+ SmallVector<const SCEV *, 4> V;
V.push_back(reinterpret_cast<const SCEV *>(-2));
return V;
}
- static unsigned getHashValue(const SmallVector<const SCEV *, 2> &V) {
- unsigned Result = 0;
- for (SmallVectorImpl<const SCEV *>::const_iterator I = V.begin(),
- E = V.end(); I != E; ++I)
- Result ^= DenseMapInfo<const SCEV *>::getHashValue(*I);
- return Result;
+ static unsigned getHashValue(const SmallVector<const SCEV *, 4> &V) {
+ return static_cast<unsigned>(hash_combine_range(V.begin(), V.end()));
}
- static bool isEqual(const SmallVector<const SCEV *, 2> &LHS,
- const SmallVector<const SCEV *, 2> &RHS) {
+ static bool isEqual(const SmallVector<const SCEV *, 4> &LHS,
+ const SmallVector<const SCEV *, 4> &RHS) {
return LHS == RHS;
}
};
/// the user itself, and information about how the use may be satisfied.
/// TODO: Represent multiple users of the same expression in common?
class LSRUse {
- DenseSet<SmallVector<const SCEV *, 2>, UniquifierDenseMapInfo> Uniquifier;
+ DenseSet<SmallVector<const SCEV *, 4>, UniquifierDenseMapInfo> Uniquifier;
public:
/// KindType - An enum for a kind of use, indicating what types of
// TODO: Add a generic icmp too?
};
+ typedef PointerIntPair<const SCEV *, 2, KindType> SCEVUseKindPair;
+
KindType Kind;
Type *AccessTy;
/// may be used.
bool AllFixupsOutsideLoop;
+ /// RigidFormula is set to true to guarantee that this use will be associated
+ /// with a single formula--the one that initially matched. Some SCEV
+ /// expressions cannot be expanded. This allows LSR to consider the registers
+ /// used by those expressions without the need to expand them later after
+ /// changing the formula.
+ bool RigidFormula;
+
/// WidestFixupType - This records the widest use type for any fixup using
/// this LSRUse. FindUseWithSimilarFormula can't consider uses with different
/// max fixup widths to be equivalent, because the narrower one may be relying
MinOffset(INT64_MAX),
MaxOffset(INT64_MIN),
AllFixupsOutsideLoop(true),
- WidestFixupType(0) {}
+ RigidFormula(false),
+ WidestFixupType(nullptr) {}
bool HasFormulaWithSameRegs(const Formula &F) const;
bool InsertFormula(const Formula &F);
/// HasFormula - Test whether this use as a formula which has the same
/// registers as the given formula.
bool LSRUse::HasFormulaWithSameRegs(const Formula &F) const {
- SmallVector<const SCEV *, 2> Key = F.BaseRegs;
+ SmallVector<const SCEV *, 4> Key = F.BaseRegs;
if (F.ScaledReg) Key.push_back(F.ScaledReg);
// Unstable sort by host order ok, because this is only used for uniquifying.
std::sort(Key.begin(), Key.end());
/// InsertFormula - If the given formula has not yet been inserted, add it to
/// the list, and return true. Return false otherwise.
+/// The formula must be in canonical form.
bool LSRUse::InsertFormula(const Formula &F) {
- SmallVector<const SCEV *, 2> Key = F.BaseRegs;
+ assert(F.isCanonical() && "Invalid canonical representation");
+
+ if (!Formulae.empty() && RigidFormula)
+ return false;
+
+ SmallVector<const SCEV *, 4> Key = F.BaseRegs;
if (F.ScaledReg) Key.push_back(F.ScaledReg);
// Unstable sort by host order ok, because this is only used for uniquifying.
std::sort(Key.begin(), Key.end());
// Record registers now being used by this use.
Regs.insert(F.BaseRegs.begin(), F.BaseRegs.end());
+ if (F.ScaledReg)
+ Regs.insert(F.ScaledReg);
return true;
}
}
// Update the RegTracker.
- for (SmallPtrSet<const SCEV *, 4>::iterator I = OldRegs.begin(),
- E = OldRegs.end(); I != E; ++I)
- if (!Regs.count(*I))
- RegUses.DropRegister(*I, LUIdx);
+ for (const SCEV *S : OldRegs)
+ if (!Regs.count(S))
+ RegUses.DropRegister(S, LUIdx);
}
void LSRUse::print(raw_ostream &OS) const {
for (SmallVectorImpl<int64_t>::const_iterator I = Offsets.begin(),
E = Offsets.end(); I != E; ++I) {
OS << *I;
- if (llvm::next(I) != E)
+ if (std::next(I) != E)
OS << ',';
}
OS << '}';
OS << ", widest fixup type: " << *WidestFixupType;
}
+#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
void LSRUse::dump() const {
print(errs()); errs() << '\n';
}
+#endif
-/// isLegalUse - Test whether the use described by AM is "legal", meaning it can
-/// be completely folded into the user instruction at isel time. This includes
-/// address-mode folding and special icmp tricks.
-static bool isLegalUse(const TargetLowering::AddrMode &AM,
- LSRUse::KindType Kind, Type *AccessTy,
- const TargetLowering *TLI) {
+static bool isAMCompletelyFolded(const TargetTransformInfo &TTI,
+ LSRUse::KindType Kind, Type *AccessTy,
+ GlobalValue *BaseGV, int64_t BaseOffset,
+ bool HasBaseReg, int64_t Scale) {
switch (Kind) {
case LSRUse::Address:
- // If we have low-level target information, ask the target if it can
- // completely fold this address.
- if (TLI) return TLI->isLegalAddressingMode(AM, AccessTy);
+ return TTI.isLegalAddressingMode(AccessTy, BaseGV, BaseOffset, HasBaseReg, Scale);
// Otherwise, just guess that reg+reg addressing is legal.
- return !AM.BaseGV && AM.BaseOffs == 0 && AM.Scale <= 1;
+ //return ;
case LSRUse::ICmpZero:
// There's not even a target hook for querying whether it would be legal to
// fold a GV into an ICmp.
- if (AM.BaseGV)
+ if (BaseGV)
return false;
// ICmp only has two operands; don't allow more than two non-trivial parts.
- if (AM.Scale != 0 && AM.HasBaseReg && AM.BaseOffs != 0)
+ if (Scale != 0 && HasBaseReg && BaseOffset != 0)
return false;
// ICmp only supports no scale or a -1 scale, as we can "fold" a -1 scale by
// putting the scaled register in the other operand of the icmp.
- if (AM.Scale != 0 && AM.Scale != -1)
+ if (Scale != 0 && Scale != -1)
return false;
// If we have low-level target information, ask the target if it can fold an
// integer immediate on an icmp.
- if (AM.BaseOffs != 0) {
- if (!TLI)
- return false;
+ if (BaseOffset != 0) {
// We have one of:
- // ICmpZero BaseReg + Offset => ICmp BaseReg, -Offset
- // ICmpZero -1*ScaleReg + Offset => ICmp ScaleReg, Offset
+ // ICmpZero BaseReg + BaseOffset => ICmp BaseReg, -BaseOffset
+ // ICmpZero -1*ScaleReg + BaseOffset => ICmp ScaleReg, BaseOffset
// Offs is the ICmp immediate.
- int64_t Offs = AM.BaseOffs;
- if (AM.Scale == 0)
- Offs = -(uint64_t)Offs; // The cast does the right thing with INT64_MIN.
- return TLI->isLegalICmpImmediate(Offs);
+ if (Scale == 0)
+ // The cast does the right thing with INT64_MIN.
+ BaseOffset = -(uint64_t)BaseOffset;
+ return TTI.isLegalICmpImmediate(BaseOffset);
}
// ICmpZero BaseReg + -1*ScaleReg => ICmp BaseReg, ScaleReg
case LSRUse::Basic:
// Only handle single-register values.
- return !AM.BaseGV && AM.Scale == 0 && AM.BaseOffs == 0;
+ return !BaseGV && Scale == 0 && BaseOffset == 0;
case LSRUse::Special:
// Special case Basic to handle -1 scales.
- return !AM.BaseGV && (AM.Scale == 0 || AM.Scale == -1) && AM.BaseOffs == 0;
+ return !BaseGV && (Scale == 0 || Scale == -1) && BaseOffset == 0;
}
llvm_unreachable("Invalid LSRUse Kind!");
}
-static bool isLegalUse(TargetLowering::AddrMode AM,
- int64_t MinOffset, int64_t MaxOffset,
- LSRUse::KindType Kind, Type *AccessTy,
- const TargetLowering *TLI) {
+static bool isAMCompletelyFolded(const TargetTransformInfo &TTI,
+ int64_t MinOffset, int64_t MaxOffset,
+ LSRUse::KindType Kind, Type *AccessTy,
+ GlobalValue *BaseGV, int64_t BaseOffset,
+ bool HasBaseReg, int64_t Scale) {
// Check for overflow.
- if (((int64_t)((uint64_t)AM.BaseOffs + MinOffset) > AM.BaseOffs) !=
+ if (((int64_t)((uint64_t)BaseOffset + MinOffset) > BaseOffset) !=
(MinOffset > 0))
return false;
- AM.BaseOffs = (uint64_t)AM.BaseOffs + MinOffset;
- if (isLegalUse(AM, Kind, AccessTy, TLI)) {
- AM.BaseOffs = (uint64_t)AM.BaseOffs - MinOffset;
- // Check for overflow.
- if (((int64_t)((uint64_t)AM.BaseOffs + MaxOffset) > AM.BaseOffs) !=
- (MaxOffset > 0))
- return false;
- AM.BaseOffs = (uint64_t)AM.BaseOffs + MaxOffset;
- return isLegalUse(AM, Kind, AccessTy, TLI);
+ MinOffset = (uint64_t)BaseOffset + MinOffset;
+ if (((int64_t)((uint64_t)BaseOffset + MaxOffset) > BaseOffset) !=
+ (MaxOffset > 0))
+ return false;
+ MaxOffset = (uint64_t)BaseOffset + MaxOffset;
+
+ return isAMCompletelyFolded(TTI, Kind, AccessTy, BaseGV, MinOffset,
+ HasBaseReg, Scale) &&
+ isAMCompletelyFolded(TTI, Kind, AccessTy, BaseGV, MaxOffset,
+ HasBaseReg, Scale);
+}
+
+static bool isAMCompletelyFolded(const TargetTransformInfo &TTI,
+ int64_t MinOffset, int64_t MaxOffset,
+ LSRUse::KindType Kind, Type *AccessTy,
+ const Formula &F) {
+ // For the purpose of isAMCompletelyFolded either having a canonical formula
+ // or a scale not equal to zero is correct.
+ // Problems may arise from non canonical formulae having a scale == 0.
+ // Strictly speaking it would best to just rely on canonical formulae.
+ // However, when we generate the scaled formulae, we first check that the
+ // scaling factor is profitable before computing the actual ScaledReg for
+ // compile time sake.
+ assert((F.isCanonical() || F.Scale != 0));
+ return isAMCompletelyFolded(TTI, MinOffset, MaxOffset, Kind, AccessTy,
+ F.BaseGV, F.BaseOffset, F.HasBaseReg, F.Scale);
+}
+
+/// isLegalUse - Test whether we know how to expand the current formula.
+static bool isLegalUse(const TargetTransformInfo &TTI, int64_t MinOffset,
+ int64_t MaxOffset, LSRUse::KindType Kind, Type *AccessTy,
+ GlobalValue *BaseGV, int64_t BaseOffset, bool HasBaseReg,
+ int64_t Scale) {
+ // We know how to expand completely foldable formulae.
+ return isAMCompletelyFolded(TTI, MinOffset, MaxOffset, Kind, AccessTy, BaseGV,
+ BaseOffset, HasBaseReg, Scale) ||
+ // Or formulae that use a base register produced by a sum of base
+ // registers.
+ (Scale == 1 &&
+ isAMCompletelyFolded(TTI, MinOffset, MaxOffset, Kind, AccessTy,
+ BaseGV, BaseOffset, true, 0));
+}
+
+static bool isLegalUse(const TargetTransformInfo &TTI, int64_t MinOffset,
+ int64_t MaxOffset, LSRUse::KindType Kind, Type *AccessTy,
+ const Formula &F) {
+ return isLegalUse(TTI, MinOffset, MaxOffset, Kind, AccessTy, F.BaseGV,
+ F.BaseOffset, F.HasBaseReg, F.Scale);
+}
+
+static bool isAMCompletelyFolded(const TargetTransformInfo &TTI,
+ const LSRUse &LU, const Formula &F) {
+ return isAMCompletelyFolded(TTI, LU.MinOffset, LU.MaxOffset, LU.Kind,
+ LU.AccessTy, F.BaseGV, F.BaseOffset, F.HasBaseReg,
+ F.Scale);
+}
+
+static unsigned getScalingFactorCost(const TargetTransformInfo &TTI,
+ const LSRUse &LU, const Formula &F) {
+ if (!F.Scale)
+ return 0;
+
+ // If the use is not completely folded in that instruction, we will have to
+ // pay an extra cost only for scale != 1.
+ if (!isAMCompletelyFolded(TTI, LU.MinOffset, LU.MaxOffset, LU.Kind,
+ LU.AccessTy, F))
+ return F.Scale != 1;
+
+ switch (LU.Kind) {
+ case LSRUse::Address: {
+ // Check the scaling factor cost with both the min and max offsets.
+ int ScaleCostMinOffset =
+ TTI.getScalingFactorCost(LU.AccessTy, F.BaseGV,
+ F.BaseOffset + LU.MinOffset,
+ F.HasBaseReg, F.Scale);
+ int ScaleCostMaxOffset =
+ TTI.getScalingFactorCost(LU.AccessTy, F.BaseGV,
+ F.BaseOffset + LU.MaxOffset,
+ F.HasBaseReg, F.Scale);
+
+ assert(ScaleCostMinOffset >= 0 && ScaleCostMaxOffset >= 0 &&
+ "Legal addressing mode has an illegal cost!");
+ return std::max(ScaleCostMinOffset, ScaleCostMaxOffset);
}
- return false;
+ case LSRUse::ICmpZero:
+ case LSRUse::Basic:
+ case LSRUse::Special:
+ // The use is completely folded, i.e., everything is folded into the
+ // instruction.
+ return 0;
+ }
+
+ llvm_unreachable("Invalid LSRUse Kind!");
}
-static bool isAlwaysFoldable(int64_t BaseOffs,
- GlobalValue *BaseGV,
- bool HasBaseReg,
+static bool isAlwaysFoldable(const TargetTransformInfo &TTI,
LSRUse::KindType Kind, Type *AccessTy,
- const TargetLowering *TLI) {
+ GlobalValue *BaseGV, int64_t BaseOffset,
+ bool HasBaseReg) {
// Fast-path: zero is always foldable.
- if (BaseOffs == 0 && !BaseGV) return true;
+ if (BaseOffset == 0 && !BaseGV) return true;
// Conservatively, create an address with an immediate and a
// base and a scale.
- TargetLowering::AddrMode AM;
- AM.BaseOffs = BaseOffs;
- AM.BaseGV = BaseGV;
- AM.HasBaseReg = HasBaseReg;
- AM.Scale = Kind == LSRUse::ICmpZero ? -1 : 1;
+ int64_t Scale = Kind == LSRUse::ICmpZero ? -1 : 1;
// Canonicalize a scale of 1 to a base register if the formula doesn't
// already have a base register.
- if (!AM.HasBaseReg && AM.Scale == 1) {
- AM.Scale = 0;
- AM.HasBaseReg = true;
+ if (!HasBaseReg && Scale == 1) {
+ Scale = 0;
+ HasBaseReg = true;
}
- return isLegalUse(AM, Kind, AccessTy, TLI);
+ return isAMCompletelyFolded(TTI, Kind, AccessTy, BaseGV, BaseOffset,
+ HasBaseReg, Scale);
}
-static bool isAlwaysFoldable(const SCEV *S,
- int64_t MinOffset, int64_t MaxOffset,
- bool HasBaseReg,
- LSRUse::KindType Kind, Type *AccessTy,
- const TargetLowering *TLI,
- ScalarEvolution &SE) {
+static bool isAlwaysFoldable(const TargetTransformInfo &TTI,
+ ScalarEvolution &SE, int64_t MinOffset,
+ int64_t MaxOffset, LSRUse::KindType Kind,
+ Type *AccessTy, const SCEV *S, bool HasBaseReg) {
// Fast-path: zero is always foldable.
if (S->isZero()) return true;
// Conservatively, create an address with an immediate and a
// base and a scale.
- int64_t BaseOffs = ExtractImmediate(S, SE);
+ int64_t BaseOffset = ExtractImmediate(S, SE);
GlobalValue *BaseGV = ExtractSymbol(S, SE);
// If there's anything else involved, it's not foldable.
if (!S->isZero()) return false;
// Fast-path: zero is always foldable.
- if (BaseOffs == 0 && !BaseGV) return true;
+ if (BaseOffset == 0 && !BaseGV) return true;
// Conservatively, create an address with an immediate and a
// base and a scale.
- TargetLowering::AddrMode AM;
- AM.BaseOffs = BaseOffs;
- AM.BaseGV = BaseGV;
- AM.HasBaseReg = HasBaseReg;
- AM.Scale = Kind == LSRUse::ICmpZero ? -1 : 1;
+ int64_t Scale = Kind == LSRUse::ICmpZero ? -1 : 1;
- return isLegalUse(AM, MinOffset, MaxOffset, Kind, AccessTy, TLI);
+ return isAMCompletelyFolded(TTI, MinOffset, MaxOffset, Kind, AccessTy, BaseGV,
+ BaseOffset, HasBaseReg, Scale);
}
namespace {
-/// UseMapDenseMapInfo - A DenseMapInfo implementation for holding
-/// DenseMaps and DenseSets of pairs of const SCEV* and LSRUse::Kind.
-struct UseMapDenseMapInfo {
- static std::pair<const SCEV *, LSRUse::KindType> getEmptyKey() {
- return std::make_pair(reinterpret_cast<const SCEV *>(-1), LSRUse::Basic);
- }
-
- static std::pair<const SCEV *, LSRUse::KindType> getTombstoneKey() {
- return std::make_pair(reinterpret_cast<const SCEV *>(-2), LSRUse::Basic);
- }
-
- static unsigned
- getHashValue(const std::pair<const SCEV *, LSRUse::KindType> &V) {
- unsigned Result = DenseMapInfo<const SCEV *>::getHashValue(V.first);
- Result ^= DenseMapInfo<unsigned>::getHashValue(unsigned(V.second));
- return Result;
- }
-
- static bool isEqual(const std::pair<const SCEV *, LSRUse::KindType> &LHS,
- const std::pair<const SCEV *, LSRUse::KindType> &RHS) {
- return LHS == RHS;
- }
-};
-
/// IVInc - An individual increment in a Chain of IV increments.
/// Relate an IV user to an expression that computes the IV it uses from the IV
/// used by the previous link in the Chain.
SmallVector<IVInc,1> Incs;
const SCEV *ExprBase;
- IVChain() : ExprBase(0) {}
+ IVChain() : ExprBase(nullptr) {}
IVChain(const IVInc &Head, const SCEV *Base)
: Incs(1, Head), ExprBase(Base) {}
// begin - return the first increment in the chain.
const_iterator begin() const {
assert(!Incs.empty());
- return llvm::next(Incs.begin());
+ return std::next(Incs.begin());
}
const_iterator end() const {
return Incs.end();
ScalarEvolution &SE;
DominatorTree &DT;
LoopInfo &LI;
- const TargetLowering *const TLI;
+ const TargetTransformInfo &TTI;
Loop *const L;
bool Changed;
}
// Support for sharing of LSRUses between LSRFixups.
- typedef DenseMap<std::pair<const SCEV *, LSRUse::KindType>,
- size_t,
- UseMapDenseMapInfo> UseMapTy;
+ typedef DenseMap<LSRUse::SCEVUseKindPair, size_t> UseMapTy;
UseMapTy UseMap;
bool reconcileNewOffset(LSRUse &LU, int64_t NewOffset, bool HasBaseReg,
void GenerateReassociations(LSRUse &LU, unsigned LUIdx, Formula Base,
unsigned Depth = 0);
+
+ void GenerateReassociationsImpl(LSRUse &LU, unsigned LUIdx,
+ const Formula &Base, unsigned Depth,
+ size_t Idx, bool IsScaledReg = false);
void GenerateCombinations(LSRUse &LU, unsigned LUIdx, Formula Base);
+ void GenerateSymbolicOffsetsImpl(LSRUse &LU, unsigned LUIdx,
+ const Formula &Base, size_t Idx,
+ bool IsScaledReg = false);
void GenerateSymbolicOffsets(LSRUse &LU, unsigned LUIdx, Formula Base);
+ void GenerateConstantOffsetsImpl(LSRUse &LU, unsigned LUIdx,
+ const Formula &Base,
+ const SmallVectorImpl<int64_t> &Worklist,
+ size_t Idx, bool IsScaledReg = false);
void GenerateConstantOffsets(LSRUse &LU, unsigned LUIdx, Formula Base);
void GenerateICmpZeroScales(LSRUse &LU, unsigned LUIdx, Formula Base);
void GenerateScales(LSRUse &LU, unsigned LUIdx, Formula Base);
Pass *P);
public:
- LSRInstance(const TargetLowering *tli, Loop *l, Pass *P);
+ LSRInstance(Loop *L, Pass *P);
bool getChanged() const { return Changed; }
IVUsers::const_iterator CandidateUI = UI;
++UI;
Instruction *ShadowUse = CandidateUI->getUser();
- Type *DestTy = NULL;
+ Type *DestTy = nullptr;
bool IsSigned = false;
/* If shadow use is a int->float cast then insert a second IV
}
if (!DestTy) continue;
- if (TLI) {
- // If target does not support DestTy natively then do not apply
- // this transformation.
- EVT DVT = TLI->getValueType(DestTy);
- if (!TLI->isTypeLegal(DVT)) continue;
- }
+ // If target does not support DestTy natively then do not apply
+ // this transformation.
+ if (!TTI.isTypeLegal(DestTy)) continue;
PHINode *PH = dyn_cast<PHINode>(ShadowUse->getOperand(0));
if (!PH) continue;
continue;
/* Initialize new IV, double d = 0.0 in above example. */
- ConstantInt *C = NULL;
+ ConstantInt *C = nullptr;
if (Incr->getOperand(0) == PH)
C = dyn_cast<ConstantInt>(Incr->getOperand(1));
else if (Incr->getOperand(1) == PH)
// for ICMP_ULE here because the comparison would be with zero, which
// isn't interesting.
CmpInst::Predicate Pred = ICmpInst::BAD_ICMP_PREDICATE;
- const SCEVNAryExpr *Max = 0;
+ const SCEVNAryExpr *Max = nullptr;
if (const SCEVSMaxExpr *S = dyn_cast<SCEVSMaxExpr>(BackedgeTakenCount)) {
Pred = ICmpInst::ICMP_SLE;
Max = S;
// Check the right operand of the select, and remember it, as it will
// be used in the new comparison instruction.
- Value *NewRHS = 0;
+ Value *NewRHS = nullptr;
if (ICmpInst::isTrueWhenEqual(Pred)) {
// Look for n+1, and grab n.
if (AddOperator *BO = dyn_cast<AddOperator>(Sel->getOperand(1)))
- if (isa<ConstantInt>(BO->getOperand(1)) &&
- cast<ConstantInt>(BO->getOperand(1))->isOne() &&
- SE.getSCEV(BO->getOperand(0)) == MaxRHS)
- NewRHS = BO->getOperand(0);
+ if (ConstantInt *BO1 = dyn_cast<ConstantInt>(BO->getOperand(1)))
+ if (BO1->isOne() && SE.getSCEV(BO->getOperand(0)) == MaxRHS)
+ NewRHS = BO->getOperand(0);
if (AddOperator *BO = dyn_cast<AddOperator>(Sel->getOperand(2)))
- if (isa<ConstantInt>(BO->getOperand(1)) &&
- cast<ConstantInt>(BO->getOperand(1))->isOne() &&
- SE.getSCEV(BO->getOperand(0)) == MaxRHS)
- NewRHS = BO->getOperand(0);
+ if (ConstantInt *BO1 = dyn_cast<ConstantInt>(BO->getOperand(1)))
+ if (BO1->isOne() && SE.getSCEV(BO->getOperand(0)) == MaxRHS)
+ NewRHS = BO->getOperand(0);
if (!NewRHS)
return Cond;
} else if (SE.getSCEV(Sel->getOperand(1)) == MaxRHS)
continue;
// Search IVUsesByStride to find Cond's IVUse if there is one.
- IVStrideUse *CondUse = 0;
+ IVStrideUse *CondUse = nullptr;
ICmpInst *Cond = cast<ICmpInst>(TermBr->getCondition());
if (!FindIVUserForCond(Cond, CondUse))
continue;
if (C->getValue().getMinSignedBits() >= 64 ||
C->getValue().isMinSignedValue())
goto decline_post_inc;
- // Without TLI, assume that any stride might be valid, and so any
- // use might be shared.
- if (!TLI)
- goto decline_post_inc;
// Check for possible scaled-address reuse.
Type *AccessTy = getAccessType(UI->getUser());
- TargetLowering::AddrMode AM;
- AM.Scale = C->getSExtValue();
- if (TLI->isLegalAddressingMode(AM, AccessTy))
+ int64_t Scale = C->getSExtValue();
+ if (TTI.isLegalAddressingMode(AccessTy, /*BaseGV=*/ nullptr,
+ /*BaseOffset=*/ 0,
+ /*HasBaseReg=*/ false, Scale))
goto decline_post_inc;
- AM.Scale = -AM.Scale;
- if (TLI->isLegalAddressingMode(AM, AccessTy))
+ Scale = -Scale;
+ if (TTI.isLegalAddressingMode(AccessTy, /*BaseGV=*/ nullptr,
+ /*BaseOffset=*/ 0,
+ /*HasBaseReg=*/ false, Scale))
goto decline_post_inc;
}
}
// must dominate all the post-inc comparisons we just set up, and it must
// dominate the loop latch edge.
IVIncInsertPos = L->getLoopLatch()->getTerminator();
- for (SmallPtrSet<Instruction *, 4>::const_iterator I = PostIncs.begin(),
- E = PostIncs.end(); I != E; ++I) {
+ for (Instruction *Inst : PostIncs) {
BasicBlock *BB =
DT.findNearestCommonDominator(IVIncInsertPos->getParent(),
- (*I)->getParent());
- if (BB == (*I)->getParent())
- IVIncInsertPos = *I;
+ Inst->getParent());
+ if (BB == Inst->getParent())
+ IVIncInsertPos = Inst;
else if (BB != IVIncInsertPos->getParent())
IVIncInsertPos = BB->getTerminator();
}
// the uses will have all its uses outside the loop, for example.
if (LU.Kind != Kind)
return false;
+
+ // Check for a mismatched access type, and fall back conservatively as needed.
+ // TODO: Be less conservative when the type is similar and can use the same
+ // addressing modes.
+ if (Kind == LSRUse::Address && AccessTy != LU.AccessTy)
+ NewAccessTy = Type::getVoidTy(AccessTy->getContext());
+
// Conservatively assume HasBaseReg is true for now.
if (NewOffset < LU.MinOffset) {
- if (!isAlwaysFoldable(LU.MaxOffset - NewOffset, 0, HasBaseReg,
- Kind, AccessTy, TLI))
+ if (!isAlwaysFoldable(TTI, Kind, NewAccessTy, /*BaseGV=*/nullptr,
+ LU.MaxOffset - NewOffset, HasBaseReg))
return false;
NewMinOffset = NewOffset;
} else if (NewOffset > LU.MaxOffset) {
- if (!isAlwaysFoldable(NewOffset - LU.MinOffset, 0, HasBaseReg,
- Kind, AccessTy, TLI))
+ if (!isAlwaysFoldable(TTI, Kind, NewAccessTy, /*BaseGV=*/nullptr,
+ NewOffset - LU.MinOffset, HasBaseReg))
return false;
NewMaxOffset = NewOffset;
}
- // Check for a mismatched access type, and fall back conservatively as needed.
- // TODO: Be less conservative when the type is similar and can use the same
- // addressing modes.
- if (Kind == LSRUse::Address && AccessTy != LU.AccessTy)
- NewAccessTy = Type::getVoidTy(AccessTy->getContext());
// Update the use.
LU.MinOffset = NewMinOffset;
int64_t Offset = ExtractImmediate(Expr, SE);
// Basic uses can't accept any offset, for example.
- if (!isAlwaysFoldable(Offset, 0, /*HasBaseReg=*/true, Kind, AccessTy, TLI)) {
+ if (!isAlwaysFoldable(TTI, Kind, AccessTy, /*BaseGV=*/ nullptr,
+ Offset, /*HasBaseReg=*/ true)) {
Expr = Copy;
Offset = 0;
}
std::pair<UseMapTy::iterator, bool> P =
- UseMap.insert(std::make_pair(std::make_pair(Expr, Kind), 0));
+ UseMap.insert(std::make_pair(LSRUse::SCEVUseKindPair(Expr, Kind), 0));
if (!P.second) {
// A use already existed with this base.
size_t LUIdx = P.first->second;
// as OrigF.
if (F.BaseRegs == OrigF.BaseRegs &&
F.ScaledReg == OrigF.ScaledReg &&
- F.AM.BaseGV == OrigF.AM.BaseGV &&
- F.AM.Scale == OrigF.AM.Scale &&
+ F.BaseGV == OrigF.BaseGV &&
+ F.Scale == OrigF.Scale &&
F.UnfoldedOffset == OrigF.UnfoldedOffset) {
- if (F.AM.BaseOffs == 0)
+ if (F.BaseOffset == 0)
return &LU;
// This is the formula where all the registers and symbols matched;
// there aren't going to be any others. Since we declined it, we
}
// Nothing looked good.
- return 0;
+ return nullptr;
}
void LSRInstance::CollectInterestingTypesAndFactors() {
for (SmallSetVector<const SCEV *, 4>::const_iterator
I = Strides.begin(), E = Strides.end(); I != E; ++I)
for (SmallSetVector<const SCEV *, 4>::const_iterator NewStrideIter =
- llvm::next(I); NewStrideIter != E; ++NewStrideIter) {
+ std::next(I); NewStrideIter != E; ++NewStrideIter) {
const SCEV *OldStride = *I;
const SCEV *NewStride = *NewStrideIter;
default: // uncluding scUnknown.
return S;
case scConstant:
- return 0;
+ return nullptr;
case scTruncate:
return getExprBase(cast<SCEVTruncateExpr>(S)->getOperand());
case scZeroExtend:
///
/// TODO: Consider IVInc free if it's already used in another chains.
static bool
-isProfitableChain(IVChain &Chain, SmallPtrSet<Instruction*, 4> &Users,
- ScalarEvolution &SE, const TargetLowering *TLI) {
+isProfitableChain(IVChain &Chain, SmallPtrSetImpl<Instruction*> &Users,
+ ScalarEvolution &SE, const TargetTransformInfo &TTI) {
if (StressIVChain)
return true;
if (!Users.empty()) {
DEBUG(dbgs() << "Chain: " << *Chain.Incs[0].UserInst << " users:\n";
- for (SmallPtrSet<Instruction*, 4>::const_iterator I = Users.begin(),
- E = Users.end(); I != E; ++I) {
- dbgs() << " " << **I << "\n";
+ for (Instruction *Inst : Users) {
+ dbgs() << " " << *Inst << "\n";
});
return false;
}
&& SE.getSCEV(Chain.tailUserInst()) == Chain.Incs[0].IncExpr) {
--cost;
}
- const SCEV *LastIncExpr = 0;
+ const SCEV *LastIncExpr = nullptr;
unsigned NumConstIncrements = 0;
unsigned NumVarIncrements = 0;
unsigned NumReusedIncrements = 0;
// Visit all existing chains. Check if its IVOper can be computed as a
// profitable loop invariant increment from the last link in the Chain.
unsigned ChainIdx = 0, NChains = IVChainVec.size();
- const SCEV *LastIncExpr = 0;
+ const SCEV *LastIncExpr = nullptr;
for (; ChainIdx < NChains; ++ChainIdx) {
IVChain &Chain = IVChainVec[ChainIdx];
// Add this IV user to the end of the chain.
IVChainVec[ChainIdx].add(IVInc(UserInst, IVOper, LastIncExpr));
}
+ IVChain &Chain = IVChainVec[ChainIdx];
SmallPtrSet<Instruction*,4> &NearUsers = ChainUsersVec[ChainIdx].NearUsers;
// This chain's NearUsers become FarUsers.
// they will eventually be used be the current chain, or can be computed
// from one of the chain increments. To be more precise we could
// transitively follow its user and only add leaf IV users to the set.
- for (Value::use_iterator UseIter = IVOper->use_begin(),
- UseEnd = IVOper->use_end(); UseIter != UseEnd; ++UseIter) {
- Instruction *OtherUse = dyn_cast<Instruction>(*UseIter);
- if (!OtherUse || OtherUse == UserInst)
+ for (User *U : IVOper->users()) {
+ Instruction *OtherUse = dyn_cast<Instruction>(U);
+ if (!OtherUse)
continue;
+ // Uses in the chain will no longer be uses if the chain is formed.
+ // Include the head of the chain in this iteration (not Chain.begin()).
+ IVChain::const_iterator IncIter = Chain.Incs.begin();
+ IVChain::const_iterator IncEnd = Chain.Incs.end();
+ for( ; IncIter != IncEnd; ++IncIter) {
+ if (IncIter->UserInst == OtherUse)
+ break;
+ }
+ if (IncIter != IncEnd)
+ continue;
+
if (SE.isSCEVable(OtherUse->getType())
&& !isa<SCEVUnknown>(SE.getSCEV(OtherUse))
&& IU.isIVUserOrOperand(OtherUse)) {
Instruction *IVOpInst = cast<Instruction>(*IVOpIter);
if (UniqueOperands.insert(IVOpInst))
ChainInstruction(I, IVOpInst, ChainUsersVec);
- IVOpIter = findIVOperand(llvm::next(IVOpIter), IVOpEnd, L, SE);
+ IVOpIter = findIVOperand(std::next(IVOpIter), IVOpEnd, L, SE);
}
} // Continue walking down the instructions.
} // Continue walking down the domtree.
for (unsigned UsersIdx = 0, NChains = IVChainVec.size();
UsersIdx < NChains; ++UsersIdx) {
if (!isProfitableChain(IVChainVec[UsersIdx],
- ChainUsersVec[UsersIdx].FarUsers, SE, TLI))
+ ChainUsersVec[UsersIdx].FarUsers, SE, TTI))
continue;
// Preserve the chain at UsesIdx.
if (ChainIdx != UsersIdx)
/// Return true if the IVInc can be folded into an addressing mode.
static bool canFoldIVIncExpr(const SCEV *IncExpr, Instruction *UserInst,
- Value *Operand, const TargetLowering *TLI) {
+ Value *Operand, const TargetTransformInfo &TTI) {
const SCEVConstant *IncConst = dyn_cast<SCEVConstant>(IncExpr);
if (!IncConst || !isAddressUse(UserInst, Operand))
return false;
return false;
int64_t IncOffset = IncConst->getValue()->getSExtValue();
- if (!isAlwaysFoldable(IncOffset, /*BaseGV=*/0, /*HaseBaseReg=*/false,
- LSRUse::Address, getAccessType(UserInst), TLI))
+ if (!isAlwaysFoldable(TTI, LSRUse::Address,
+ getAccessType(UserInst), /*BaseGV=*/ nullptr,
+ IncOffset, /*HaseBaseReg=*/ false))
return false;
return true;
// by LSR.
const IVInc &Head = Chain.Incs[0];
User::op_iterator IVOpEnd = Head.UserInst->op_end();
+ // findIVOperand returns IVOpEnd if it can no longer find a valid IV user.
User::op_iterator IVOpIter = findIVOperand(Head.UserInst->op_begin(),
IVOpEnd, L, SE);
- Value *IVSrc = 0;
+ Value *IVSrc = nullptr;
while (IVOpIter != IVOpEnd) {
IVSrc = getWideOperand(*IVOpIter);
|| SE.getSCEV(IVSrc) == Head.IncExpr) {
break;
}
- IVOpIter = findIVOperand(llvm::next(IVOpIter), IVOpEnd, L, SE);
+ IVOpIter = findIVOperand(std::next(IVOpIter), IVOpEnd, L, SE);
}
if (IVOpIter == IVOpEnd) {
// Gracefully give up on this chain.
DEBUG(dbgs() << "Generate chain at: " << *IVSrc << "\n");
Type *IVTy = IVSrc->getType();
Type *IntTy = SE.getEffectiveSCEVType(IVTy);
- const SCEV *LeftOverExpr = 0;
+ const SCEV *LeftOverExpr = nullptr;
for (IVChain::const_iterator IncI = Chain.begin(),
IncE = Chain.end(); IncI != IncE; ++IncI) {
// If an IV increment can't be folded, use it as the next IV value.
if (!canFoldIVIncExpr(LeftOverExpr, IncI->UserInst, IncI->IVOperand,
- TLI)) {
+ TTI)) {
assert(IVTy == IVOper->getType() && "inconsistent IV increment type");
IVSrc = IVOper;
- LeftOverExpr = 0;
+ LeftOverExpr = nullptr;
}
}
Type *OperTy = IncI->IVOperand->getType();
LF.PostIncLoops = UI->getPostIncLoops();
LSRUse::KindType Kind = LSRUse::Basic;
- Type *AccessTy = 0;
+ Type *AccessTy = nullptr;
if (isAddressUse(LF.UserInst, LF.OperandValToReplace)) {
Kind = LSRUse::Address;
AccessTy = getAccessType(LF.UserInst);
// x == y --> x - y == 0
const SCEV *N = SE.getSCEV(NV);
- if (SE.isLoopInvariant(N, L)) {
+ if (SE.isLoopInvariant(N, L) && isSafeToExpand(N, SE)) {
// S is normalized, so normalize N before folding it into S
// to keep the result normalized.
- N = TransformForPostIncUse(Normalize, N, CI, 0,
+ N = TransformForPostIncUse(Normalize, N, CI, nullptr,
LF.PostIncLoops, SE, DT);
Kind = LSRUse::ICmpZero;
S = SE.getMinusSCEV(N, S);
/// and loop-computable portions.
void
LSRInstance::InsertInitialFormula(const SCEV *S, LSRUse &LU, size_t LUIdx) {
+ // Mark uses whose expressions cannot be expanded.
+ if (!isSafeToExpand(S, SE))
+ LU.RigidFormula = true;
+
Formula F;
F.InitialMatch(S, L, SE);
bool Inserted = InsertFormula(LU, LUIdx, F);
LSRUse &LU, size_t LUIdx) {
Formula F;
F.BaseRegs.push_back(S);
- F.AM.HasBaseReg = true;
+ F.HasBaseReg = true;
bool Inserted = InsertFormula(LU, LUIdx, F);
assert(Inserted && "Supplemental formula already exists!"); (void)Inserted;
}
/// InsertFormula - If the given formula has not yet been inserted, add it to
/// the list, and return true. Return false otherwise.
bool LSRInstance::InsertFormula(LSRUse &LU, unsigned LUIdx, const Formula &F) {
+ // Do not insert formula that we will not be able to expand.
+ assert(isLegalUse(TTI, LU.MinOffset, LU.MaxOffset, LU.Kind, LU.AccessTy, F) &&
+ "Formula is illegal");
if (!LU.InsertFormula(F))
return false;
LSRInstance::CollectLoopInvariantFixupsAndFormulae() {
SmallVector<const SCEV *, 8> Worklist(RegUses.begin(), RegUses.end());
SmallPtrSet<const SCEV *, 8> Inserted;
+ SmallPtrSet<const SCEV *, 32> Done;
while (!Worklist.empty()) {
const SCEV *S = Worklist.pop_back_val();
+ // Don't process the same SCEV twice
+ if (!Done.insert(S))
+ continue;
+
if (const SCEVNAryExpr *N = dyn_cast<SCEVNAryExpr>(S))
Worklist.append(N->op_begin(), N->op_end());
else if (const SCEVCastExpr *C = dyn_cast<SCEVCastExpr>(S))
else if (const SCEVUDivExpr *D = dyn_cast<SCEVUDivExpr>(S)) {
Worklist.push_back(D->getLHS());
Worklist.push_back(D->getRHS());
- } else if (const SCEVUnknown *U = dyn_cast<SCEVUnknown>(S)) {
- if (!Inserted.insert(U)) continue;
- const Value *V = U->getValue();
+ } else if (const SCEVUnknown *US = dyn_cast<SCEVUnknown>(S)) {
+ if (!Inserted.insert(US)) continue;
+ const Value *V = US->getValue();
if (const Instruction *Inst = dyn_cast<Instruction>(V)) {
// Look for instructions defined outside the loop.
if (L->contains(Inst)) continue;
} else if (isa<UndefValue>(V))
// Undef doesn't have a live range, so it doesn't matter.
continue;
- for (Value::const_use_iterator UI = V->use_begin(), UE = V->use_end();
- UI != UE; ++UI) {
- const Instruction *UserInst = dyn_cast<Instruction>(*UI);
+ for (const Use &U : V->uses()) {
+ const Instruction *UserInst = dyn_cast<Instruction>(U.getUser());
// Ignore non-instructions.
if (!UserInst)
continue;
const BasicBlock *UseBB = !isa<PHINode>(UserInst) ?
UserInst->getParent() :
cast<PHINode>(UserInst)->getIncomingBlock(
- PHINode::getIncomingValueNumForOperand(UI.getOperandNo()));
+ PHINode::getIncomingValueNumForOperand(U.getOperandNo()));
if (!DT.dominates(L->getHeader(), UseBB))
continue;
// Ignore uses which are part of other SCEV expressions, to avoid
// If the user is a no-op, look through to its uses.
if (!isa<SCEVUnknown>(UserS))
continue;
- if (UserS == U) {
+ if (UserS == US) {
Worklist.push_back(
SE.getUnknown(const_cast<Instruction *>(UserInst)));
continue;
}
// Ignore icmp instructions which are already being analyzed.
if (const ICmpInst *ICI = dyn_cast<ICmpInst>(UserInst)) {
- unsigned OtherIdx = !UI.getOperandNo();
+ unsigned OtherIdx = !U.getOperandNo();
Value *OtherOp = const_cast<Value *>(ICI->getOperand(OtherIdx));
if (SE.hasComputableLoopEvolution(SE.getSCEV(OtherOp), L))
continue;
LSRFixup &LF = getNewFixup();
LF.UserInst = const_cast<Instruction *>(UserInst);
- LF.OperandValToReplace = UI.getUse();
- std::pair<size_t, int64_t> P = getUse(S, LSRUse::Basic, 0);
+ LF.OperandValToReplace = U;
+ std::pair<size_t, int64_t> P = getUse(S, LSRUse::Basic, nullptr);
LF.LUIdx = P.first;
LF.Offset = P.second;
LSRUse &LU = Uses[LF.LUIdx];
SE.getTypeSizeInBits(LU.WidestFixupType) <
SE.getTypeSizeInBits(LF.OperandValToReplace->getType()))
LU.WidestFixupType = LF.OperandValToReplace->getType();
- InsertSupplementalFormula(U, LU, LF.LUIdx);
+ InsertSupplementalFormula(US, LU, LF.LUIdx);
CountRegisters(LU.Formulae.back(), Uses.size() - 1);
break;
}
/// CollectSubexprs - Split S into subexpressions which can be pulled out into
/// separate registers. If C is non-null, multiply each subexpression by C.
-static void CollectSubexprs(const SCEV *S, const SCEVConstant *C,
- SmallVectorImpl<const SCEV *> &Ops,
- const Loop *L,
- ScalarEvolution &SE) {
+///
+/// Return remainder expression after factoring the subexpressions captured by
+/// Ops. If Ops is complete, return NULL.
+static const SCEV *CollectSubexprs(const SCEV *S, const SCEVConstant *C,
+ SmallVectorImpl<const SCEV *> &Ops,
+ const Loop *L,
+ ScalarEvolution &SE,
+ unsigned Depth = 0) {
+ // Arbitrarily cap recursion to protect compile time.
+ if (Depth >= 3)
+ return S;
+
if (const SCEVAddExpr *Add = dyn_cast<SCEVAddExpr>(S)) {
// Break out add operands.
for (SCEVAddExpr::op_iterator I = Add->op_begin(), E = Add->op_end();
- I != E; ++I)
- CollectSubexprs(*I, C, Ops, L, SE);
- return;
+ I != E; ++I) {
+ const SCEV *Remainder = CollectSubexprs(*I, C, Ops, L, SE, Depth+1);
+ if (Remainder)
+ Ops.push_back(C ? SE.getMulExpr(C, Remainder) : Remainder);
+ }
+ return nullptr;
} else if (const SCEVAddRecExpr *AR = dyn_cast<SCEVAddRecExpr>(S)) {
// Split a non-zero base out of an addrec.
- if (!AR->getStart()->isZero()) {
- CollectSubexprs(SE.getAddRecExpr(SE.getConstant(AR->getType(), 0),
- AR->getStepRecurrence(SE),
- AR->getLoop(),
- //FIXME: AR->getNoWrapFlags(SCEV::FlagNW)
- SCEV::FlagAnyWrap),
- C, Ops, L, SE);
- CollectSubexprs(AR->getStart(), C, Ops, L, SE);
- return;
+ if (AR->getStart()->isZero())
+ return S;
+
+ const SCEV *Remainder = CollectSubexprs(AR->getStart(),
+ C, Ops, L, SE, Depth+1);
+ // Split the non-zero AddRec unless it is part of a nested recurrence that
+ // does not pertain to this loop.
+ if (Remainder && (AR->getLoop() == L || !isa<SCEVAddRecExpr>(Remainder))) {
+ Ops.push_back(C ? SE.getMulExpr(C, Remainder) : Remainder);
+ Remainder = nullptr;
+ }
+ if (Remainder != AR->getStart()) {
+ if (!Remainder)
+ Remainder = SE.getConstant(AR->getType(), 0);
+ return SE.getAddRecExpr(Remainder,
+ AR->getStepRecurrence(SE),
+ AR->getLoop(),
+ //FIXME: AR->getNoWrapFlags(SCEV::FlagNW)
+ SCEV::FlagAnyWrap);
}
} else if (const SCEVMulExpr *Mul = dyn_cast<SCEVMulExpr>(S)) {
// Break (C * (a + b + c)) into C*a + C*b + C*c.
- if (Mul->getNumOperands() == 2)
- if (const SCEVConstant *Op0 =
- dyn_cast<SCEVConstant>(Mul->getOperand(0))) {
- CollectSubexprs(Mul->getOperand(1),
- C ? cast<SCEVConstant>(SE.getMulExpr(C, Op0)) : Op0,
- Ops, L, SE);
- return;
- }
+ if (Mul->getNumOperands() != 2)
+ return S;
+ if (const SCEVConstant *Op0 =
+ dyn_cast<SCEVConstant>(Mul->getOperand(0))) {
+ C = C ? cast<SCEVConstant>(SE.getMulExpr(C, Op0)) : Op0;
+ const SCEV *Remainder =
+ CollectSubexprs(Mul->getOperand(1), C, Ops, L, SE, Depth+1);
+ if (Remainder)
+ Ops.push_back(SE.getMulExpr(C, Remainder));
+ return nullptr;
+ }
}
-
- // Otherwise use the value itself, optionally with a scale applied.
- Ops.push_back(C ? SE.getMulExpr(C, S) : S);
+ return S;
}
-/// GenerateReassociations - Split out subexpressions from adds and the bases of
-/// addrecs.
-void LSRInstance::GenerateReassociations(LSRUse &LU, unsigned LUIdx,
- Formula Base,
- unsigned Depth) {
- // Arbitrarily cap recursion to protect compile time.
- if (Depth >= 3) return;
+/// \brief Helper function for LSRInstance::GenerateReassociations.
+void LSRInstance::GenerateReassociationsImpl(LSRUse &LU, unsigned LUIdx,
+ const Formula &Base,
+ unsigned Depth, size_t Idx,
+ bool IsScaledReg) {
+ const SCEV *BaseReg = IsScaledReg ? Base.ScaledReg : Base.BaseRegs[Idx];
+ SmallVector<const SCEV *, 8> AddOps;
+ const SCEV *Remainder = CollectSubexprs(BaseReg, nullptr, AddOps, L, SE);
+ if (Remainder)
+ AddOps.push_back(Remainder);
+
+ if (AddOps.size() == 1)
+ return;
- for (size_t i = 0, e = Base.BaseRegs.size(); i != e; ++i) {
- const SCEV *BaseReg = Base.BaseRegs[i];
+ for (SmallVectorImpl<const SCEV *>::const_iterator J = AddOps.begin(),
+ JE = AddOps.end();
+ J != JE; ++J) {
- SmallVector<const SCEV *, 8> AddOps;
- CollectSubexprs(BaseReg, 0, AddOps, L, SE);
+ // Loop-variant "unknown" values are uninteresting; we won't be able to
+ // do anything meaningful with them.
+ if (isa<SCEVUnknown>(*J) && !SE.isLoopInvariant(*J, L))
+ continue;
- if (AddOps.size() == 1) continue;
+ // Don't pull a constant into a register if the constant could be folded
+ // into an immediate field.
+ if (isAlwaysFoldable(TTI, SE, LU.MinOffset, LU.MaxOffset, LU.Kind,
+ LU.AccessTy, *J, Base.getNumRegs() > 1))
+ continue;
- for (SmallVectorImpl<const SCEV *>::const_iterator J = AddOps.begin(),
- JE = AddOps.end(); J != JE; ++J) {
+ // Collect all operands except *J.
+ SmallVector<const SCEV *, 8> InnerAddOps(
+ ((const SmallVector<const SCEV *, 8> &)AddOps).begin(), J);
+ InnerAddOps.append(std::next(J),
+ ((const SmallVector<const SCEV *, 8> &)AddOps).end());
+
+ // Don't leave just a constant behind in a register if the constant could
+ // be folded into an immediate field.
+ if (InnerAddOps.size() == 1 &&
+ isAlwaysFoldable(TTI, SE, LU.MinOffset, LU.MaxOffset, LU.Kind,
+ LU.AccessTy, InnerAddOps[0], Base.getNumRegs() > 1))
+ continue;
- // Loop-variant "unknown" values are uninteresting; we won't be able to
- // do anything meaningful with them.
- if (isa<SCEVUnknown>(*J) && !SE.isLoopInvariant(*J, L))
- continue;
+ const SCEV *InnerSum = SE.getAddExpr(InnerAddOps);
+ if (InnerSum->isZero())
+ continue;
+ Formula F = Base;
- // Don't pull a constant into a register if the constant could be folded
- // into an immediate field.
- if (isAlwaysFoldable(*J, LU.MinOffset, LU.MaxOffset,
- Base.getNumRegs() > 1,
- LU.Kind, LU.AccessTy, TLI, SE))
- continue;
+ // Add the remaining pieces of the add back into the new formula.
+ const SCEVConstant *InnerSumSC = dyn_cast<SCEVConstant>(InnerSum);
+ if (InnerSumSC && SE.getTypeSizeInBits(InnerSumSC->getType()) <= 64 &&
+ TTI.isLegalAddImmediate((uint64_t)F.UnfoldedOffset +
+ InnerSumSC->getValue()->getZExtValue())) {
+ F.UnfoldedOffset =
+ (uint64_t)F.UnfoldedOffset + InnerSumSC->getValue()->getZExtValue();
+ if (IsScaledReg)
+ F.ScaledReg = nullptr;
+ else
+ F.BaseRegs.erase(F.BaseRegs.begin() + Idx);
+ } else if (IsScaledReg)
+ F.ScaledReg = InnerSum;
+ else
+ F.BaseRegs[Idx] = InnerSum;
+
+ // Add J as its own register, or an unfolded immediate.
+ const SCEVConstant *SC = dyn_cast<SCEVConstant>(*J);
+ if (SC && SE.getTypeSizeInBits(SC->getType()) <= 64 &&
+ TTI.isLegalAddImmediate((uint64_t)F.UnfoldedOffset +
+ SC->getValue()->getZExtValue()))
+ F.UnfoldedOffset =
+ (uint64_t)F.UnfoldedOffset + SC->getValue()->getZExtValue();
+ else
+ F.BaseRegs.push_back(*J);
+ // We may have changed the number of register in base regs, adjust the
+ // formula accordingly.
+ F.Canonicalize();
- // Collect all operands except *J.
- SmallVector<const SCEV *, 8> InnerAddOps
- (((const SmallVector<const SCEV *, 8> &)AddOps).begin(), J);
- InnerAddOps.append
- (llvm::next(J), ((const SmallVector<const SCEV *, 8> &)AddOps).end());
-
- // Don't leave just a constant behind in a register if the constant could
- // be folded into an immediate field.
- if (InnerAddOps.size() == 1 &&
- isAlwaysFoldable(InnerAddOps[0], LU.MinOffset, LU.MaxOffset,
- Base.getNumRegs() > 1,
- LU.Kind, LU.AccessTy, TLI, SE))
- continue;
+ if (InsertFormula(LU, LUIdx, F))
+ // If that formula hadn't been seen before, recurse to find more like
+ // it.
+ GenerateReassociations(LU, LUIdx, LU.Formulae.back(), Depth + 1);
+ }
+}
- const SCEV *InnerSum = SE.getAddExpr(InnerAddOps);
- if (InnerSum->isZero())
- continue;
- Formula F = Base;
+/// GenerateReassociations - Split out subexpressions from adds and the bases of
+/// addrecs.
+void LSRInstance::GenerateReassociations(LSRUse &LU, unsigned LUIdx,
+ Formula Base, unsigned Depth) {
+ assert(Base.isCanonical() && "Input must be in the canonical form");
+ // Arbitrarily cap recursion to protect compile time.
+ if (Depth >= 3)
+ return;
- // Add the remaining pieces of the add back into the new formula.
- const SCEVConstant *InnerSumSC = dyn_cast<SCEVConstant>(InnerSum);
- if (TLI && InnerSumSC &&
- SE.getTypeSizeInBits(InnerSumSC->getType()) <= 64 &&
- TLI->isLegalAddImmediate((uint64_t)F.UnfoldedOffset +
- InnerSumSC->getValue()->getZExtValue())) {
- F.UnfoldedOffset = (uint64_t)F.UnfoldedOffset +
- InnerSumSC->getValue()->getZExtValue();
- F.BaseRegs.erase(F.BaseRegs.begin() + i);
- } else
- F.BaseRegs[i] = InnerSum;
-
- // Add J as its own register, or an unfolded immediate.
- const SCEVConstant *SC = dyn_cast<SCEVConstant>(*J);
- if (TLI && SC && SE.getTypeSizeInBits(SC->getType()) <= 64 &&
- TLI->isLegalAddImmediate((uint64_t)F.UnfoldedOffset +
- SC->getValue()->getZExtValue()))
- F.UnfoldedOffset = (uint64_t)F.UnfoldedOffset +
- SC->getValue()->getZExtValue();
- else
- F.BaseRegs.push_back(*J);
+ for (size_t i = 0, e = Base.BaseRegs.size(); i != e; ++i)
+ GenerateReassociationsImpl(LU, LUIdx, Base, Depth, i);
- if (InsertFormula(LU, LUIdx, F))
- // If that formula hadn't been seen before, recurse to find more like
- // it.
- GenerateReassociations(LU, LUIdx, LU.Formulae.back(), Depth+1);
- }
- }
+ if (Base.Scale == 1)
+ GenerateReassociationsImpl(LU, LUIdx, Base, Depth,
+ /* Idx */ -1, /* IsScaledReg */ true);
}
/// GenerateCombinations - Generate a formula consisting of all of the
void LSRInstance::GenerateCombinations(LSRUse &LU, unsigned LUIdx,
Formula Base) {
// This method is only interesting on a plurality of registers.
- if (Base.BaseRegs.size() <= 1) return;
+ if (Base.BaseRegs.size() + (Base.Scale == 1) <= 1)
+ return;
+ // Flatten the representation, i.e., reg1 + 1*reg2 => reg1 + reg2, before
+ // processing the formula.
+ Base.Unscale();
Formula F = Base;
F.BaseRegs.clear();
SmallVector<const SCEV *, 4> Ops;
// rather than proceed with zero in a register.
if (!Sum->isZero()) {
F.BaseRegs.push_back(Sum);
+ F.Canonicalize();
(void)InsertFormula(LU, LUIdx, F);
}
}
}
+/// \brief Helper function for LSRInstance::GenerateSymbolicOffsets.
+void LSRInstance::GenerateSymbolicOffsetsImpl(LSRUse &LU, unsigned LUIdx,
+ const Formula &Base, size_t Idx,
+ bool IsScaledReg) {
+ const SCEV *G = IsScaledReg ? Base.ScaledReg : Base.BaseRegs[Idx];
+ GlobalValue *GV = ExtractSymbol(G, SE);
+ if (G->isZero() || !GV)
+ return;
+ Formula F = Base;
+ F.BaseGV = GV;
+ if (!isLegalUse(TTI, LU.MinOffset, LU.MaxOffset, LU.Kind, LU.AccessTy, F))
+ return;
+ if (IsScaledReg)
+ F.ScaledReg = G;
+ else
+ F.BaseRegs[Idx] = G;
+ (void)InsertFormula(LU, LUIdx, F);
+}
+
/// GenerateSymbolicOffsets - Generate reuse formulae using symbolic offsets.
void LSRInstance::GenerateSymbolicOffsets(LSRUse &LU, unsigned LUIdx,
Formula Base) {
// We can't add a symbolic offset if the address already contains one.
- if (Base.AM.BaseGV) return;
+ if (Base.BaseGV) return;
- for (size_t i = 0, e = Base.BaseRegs.size(); i != e; ++i) {
- const SCEV *G = Base.BaseRegs[i];
- GlobalValue *GV = ExtractSymbol(G, SE);
- if (G->isZero() || !GV)
- continue;
+ for (size_t i = 0, e = Base.BaseRegs.size(); i != e; ++i)
+ GenerateSymbolicOffsetsImpl(LU, LUIdx, Base, i);
+ if (Base.Scale == 1)
+ GenerateSymbolicOffsetsImpl(LU, LUIdx, Base, /* Idx */ -1,
+ /* IsScaledReg */ true);
+}
+
+/// \brief Helper function for LSRInstance::GenerateConstantOffsets.
+void LSRInstance::GenerateConstantOffsetsImpl(
+ LSRUse &LU, unsigned LUIdx, const Formula &Base,
+ const SmallVectorImpl<int64_t> &Worklist, size_t Idx, bool IsScaledReg) {
+ const SCEV *G = IsScaledReg ? Base.ScaledReg : Base.BaseRegs[Idx];
+ for (SmallVectorImpl<int64_t>::const_iterator I = Worklist.begin(),
+ E = Worklist.end();
+ I != E; ++I) {
Formula F = Base;
- F.AM.BaseGV = GV;
- if (!isLegalUse(F.AM, LU.MinOffset, LU.MaxOffset,
- LU.Kind, LU.AccessTy, TLI))
- continue;
- F.BaseRegs[i] = G;
- (void)InsertFormula(LU, LUIdx, F);
+ F.BaseOffset = (uint64_t)Base.BaseOffset - *I;
+ if (isLegalUse(TTI, LU.MinOffset - *I, LU.MaxOffset - *I, LU.Kind,
+ LU.AccessTy, F)) {
+ // Add the offset to the base register.
+ const SCEV *NewG = SE.getAddExpr(SE.getConstant(G->getType(), *I), G);
+ // If it cancelled out, drop the base register, otherwise update it.
+ if (NewG->isZero()) {
+ if (IsScaledReg) {
+ F.Scale = 0;
+ F.ScaledReg = nullptr;
+ } else
+ F.DeleteBaseReg(F.BaseRegs[Idx]);
+ F.Canonicalize();
+ } else if (IsScaledReg)
+ F.ScaledReg = NewG;
+ else
+ F.BaseRegs[Idx] = NewG;
+
+ (void)InsertFormula(LU, LUIdx, F);
+ }
}
+
+ int64_t Imm = ExtractImmediate(G, SE);
+ if (G->isZero() || Imm == 0)
+ return;
+ Formula F = Base;
+ F.BaseOffset = (uint64_t)F.BaseOffset + Imm;
+ if (!isLegalUse(TTI, LU.MinOffset, LU.MaxOffset, LU.Kind, LU.AccessTy, F))
+ return;
+ if (IsScaledReg)
+ F.ScaledReg = G;
+ else
+ F.BaseRegs[Idx] = G;
+ (void)InsertFormula(LU, LUIdx, F);
}
/// GenerateConstantOffsets - Generate reuse formulae using symbolic offsets.
if (LU.MaxOffset != LU.MinOffset)
Worklist.push_back(LU.MaxOffset);
- for (size_t i = 0, e = Base.BaseRegs.size(); i != e; ++i) {
- const SCEV *G = Base.BaseRegs[i];
-
- for (SmallVectorImpl<int64_t>::const_iterator I = Worklist.begin(),
- E = Worklist.end(); I != E; ++I) {
- Formula F = Base;
- F.AM.BaseOffs = (uint64_t)Base.AM.BaseOffs - *I;
- if (isLegalUse(F.AM, LU.MinOffset - *I, LU.MaxOffset - *I,
- LU.Kind, LU.AccessTy, TLI)) {
- // Add the offset to the base register.
- const SCEV *NewG = SE.getAddExpr(SE.getConstant(G->getType(), *I), G);
- // If it cancelled out, drop the base register, otherwise update it.
- if (NewG->isZero()) {
- std::swap(F.BaseRegs[i], F.BaseRegs.back());
- F.BaseRegs.pop_back();
- } else
- F.BaseRegs[i] = NewG;
-
- (void)InsertFormula(LU, LUIdx, F);
- }
- }
-
- int64_t Imm = ExtractImmediate(G, SE);
- if (G->isZero() || Imm == 0)
- continue;
- Formula F = Base;
- F.AM.BaseOffs = (uint64_t)F.AM.BaseOffs + Imm;
- if (!isLegalUse(F.AM, LU.MinOffset, LU.MaxOffset,
- LU.Kind, LU.AccessTy, TLI))
- continue;
- F.BaseRegs[i] = G;
- (void)InsertFormula(LU, LUIdx, F);
- }
+ for (size_t i = 0, e = Base.BaseRegs.size(); i != e; ++i)
+ GenerateConstantOffsetsImpl(LU, LUIdx, Base, Worklist, i);
+ if (Base.Scale == 1)
+ GenerateConstantOffsetsImpl(LU, LUIdx, Base, Worklist, /* Idx */ -1,
+ /* IsScaledReg */ true);
}
/// GenerateICmpZeroScales - For ICmpZero, check to see if we can scale up
// Don't do this if there is more than one offset.
if (LU.MinOffset != LU.MaxOffset) return;
- assert(!Base.AM.BaseGV && "ICmpZero use is not legal!");
+ assert(!Base.BaseGV && "ICmpZero use is not legal!");
// Check each interesting stride.
for (SmallSetVector<int64_t, 8>::const_iterator
int64_t Factor = *I;
// Check that the multiplication doesn't overflow.
- if (Base.AM.BaseOffs == INT64_MIN && Factor == -1)
+ if (Base.BaseOffset == INT64_MIN && Factor == -1)
+ continue;
+ int64_t NewBaseOffset = (uint64_t)Base.BaseOffset * Factor;
+ if (NewBaseOffset / Factor != Base.BaseOffset)
continue;
- int64_t NewBaseOffs = (uint64_t)Base.AM.BaseOffs * Factor;
- if (NewBaseOffs / Factor != Base.AM.BaseOffs)
+ // If the offset will be truncated at this use, check that it is in bounds.
+ if (!IntTy->isPointerTy() &&
+ !ConstantInt::isValueValidForType(IntTy, NewBaseOffset))
continue;
// Check that multiplying with the use offset doesn't overflow.
Offset = (uint64_t)Offset * Factor;
if (Offset / Factor != LU.MinOffset)
continue;
+ // If the offset will be truncated at this use, check that it is in bounds.
+ if (!IntTy->isPointerTy() &&
+ !ConstantInt::isValueValidForType(IntTy, Offset))
+ continue;
Formula F = Base;
- F.AM.BaseOffs = NewBaseOffs;
+ F.BaseOffset = NewBaseOffset;
// Check that this scale is legal.
- if (!isLegalUse(F.AM, Offset, Offset, LU.Kind, LU.AccessTy, TLI))
+ if (!isLegalUse(TTI, Offset, Offset, LU.Kind, LU.AccessTy, F))
continue;
// Compensate for the use having MinOffset built into it.
- F.AM.BaseOffs = (uint64_t)F.AM.BaseOffs + Offset - LU.MinOffset;
+ F.BaseOffset = (uint64_t)F.BaseOffset + Offset - LU.MinOffset;
const SCEV *FactorS = SE.getConstant(IntTy, Factor);
F.UnfoldedOffset = (uint64_t)F.UnfoldedOffset * Factor;
if (F.UnfoldedOffset / Factor != Base.UnfoldedOffset)
continue;
+ // If the offset will be truncated, check that it is in bounds.
+ if (!IntTy->isPointerTy() &&
+ !ConstantInt::isValueValidForType(IntTy, F.UnfoldedOffset))
+ continue;
}
// If we make it here and it's legal, add it.
if (!IntTy) return;
// If this Formula already has a scaled register, we can't add another one.
- if (Base.AM.Scale != 0) return;
+ // Try to unscale the formula to generate a better scale.
+ if (Base.Scale != 0 && !Base.Unscale())
+ return;
+
+ assert(Base.Scale == 0 && "Unscale did not did its job!");
// Check each interesting stride.
for (SmallSetVector<int64_t, 8>::const_iterator
I = Factors.begin(), E = Factors.end(); I != E; ++I) {
int64_t Factor = *I;
- Base.AM.Scale = Factor;
- Base.AM.HasBaseReg = Base.BaseRegs.size() > 1;
+ Base.Scale = Factor;
+ Base.HasBaseReg = Base.BaseRegs.size() > 1;
// Check whether this scale is going to be legal.
- if (!isLegalUse(Base.AM, LU.MinOffset, LU.MaxOffset,
- LU.Kind, LU.AccessTy, TLI)) {
+ if (!isLegalUse(TTI, LU.MinOffset, LU.MaxOffset, LU.Kind, LU.AccessTy,
+ Base)) {
// As a special-case, handle special out-of-loop Basic users specially.
// TODO: Reconsider this special case.
if (LU.Kind == LSRUse::Basic &&
- isLegalUse(Base.AM, LU.MinOffset, LU.MaxOffset,
- LSRUse::Special, LU.AccessTy, TLI) &&
+ isLegalUse(TTI, LU.MinOffset, LU.MaxOffset, LSRUse::Special,
+ LU.AccessTy, Base) &&
LU.AllFixupsOutsideLoop)
LU.Kind = LSRUse::Special;
else
// For an ICmpZero, negating a solitary base register won't lead to
// new solutions.
if (LU.Kind == LSRUse::ICmpZero &&
- !Base.AM.HasBaseReg && Base.AM.BaseOffs == 0 && !Base.AM.BaseGV)
+ !Base.HasBaseReg && Base.BaseOffset == 0 && !Base.BaseGV)
continue;
// For each addrec base reg, apply the scale, if possible.
for (size_t i = 0, e = Base.BaseRegs.size(); i != e; ++i)
Formula F = Base;
F.ScaledReg = Quotient;
F.DeleteBaseReg(F.BaseRegs[i]);
+ // The canonical representation of 1*reg is reg, which is already in
+ // Base. In that case, do not try to insert the formula, it will be
+ // rejected anyway.
+ if (F.Scale == 1 && F.BaseRegs.empty())
+ continue;
(void)InsertFormula(LU, LUIdx, F);
}
}
/// GenerateTruncates - Generate reuse formulae from different IV types.
void LSRInstance::GenerateTruncates(LSRUse &LU, unsigned LUIdx, Formula Base) {
- // This requires TargetLowering to tell us which truncates are free.
- if (!TLI) return;
-
// Don't bother truncating symbolic values.
- if (Base.AM.BaseGV) return;
+ if (Base.BaseGV) return;
// Determine the integer type for the base formula.
Type *DstTy = Base.getType();
for (SmallSetVector<Type *, 4>::const_iterator
I = Types.begin(), E = Types.end(); I != E; ++I) {
Type *SrcTy = *I;
- if (SrcTy != DstTy && TLI->isTruncateFree(SrcTy, DstTy)) {
+ if (SrcTy != DstTy && TTI.isTruncateFree(SrcTy, DstTy)) {
Formula F = Base;
if (F.ScaledReg) F.ScaledReg = SE.getAnyExtendExpr(F.ScaledReg, *I);
<< " , add offset " << Imm;
}
+#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
void WorkItem::dump() const {
print(errs()); errs() << '\n';
}
+#endif
/// GenerateCrossUseConstantOffsets - Look for registers which are a constant
/// distance apart and try to form reuse opportunities between them.
// Conservatively examine offsets between this orig reg a few selected
// other orig regs.
ImmMapTy::const_iterator OtherImms[] = {
- Imms.begin(), prior(Imms.end()),
- Imms.lower_bound((Imms.begin()->first + prior(Imms.end())->first) / 2)
+ Imms.begin(), std::prev(Imms.end()),
+ Imms.lower_bound((Imms.begin()->first + std::prev(Imms.end())->first) /
+ 2)
};
for (size_t i = 0, e = array_lengthof(OtherImms); i != e; ++i) {
ImmMapTy::const_iterator M = OtherImms[i];
// TODO: Use a more targeted data structure.
for (size_t L = 0, LE = LU.Formulae.size(); L != LE; ++L) {
- const Formula &F = LU.Formulae[L];
+ Formula F = LU.Formulae[L];
+ // FIXME: The code for the scaled and unscaled registers looks
+ // very similar but slightly different. Investigate if they
+ // could be merged. That way, we would not have to unscale the
+ // Formula.
+ F.Unscale();
// Use the immediate in the scaled register.
if (F.ScaledReg == OrigReg) {
- int64_t Offs = (uint64_t)F.AM.BaseOffs +
- Imm * (uint64_t)F.AM.Scale;
+ int64_t Offset = (uint64_t)F.BaseOffset + Imm * (uint64_t)F.Scale;
// Don't create 50 + reg(-50).
if (F.referencesReg(SE.getSCEV(
- ConstantInt::get(IntTy, -(uint64_t)Offs))))
+ ConstantInt::get(IntTy, -(uint64_t)Offset))))
continue;
Formula NewF = F;
- NewF.AM.BaseOffs = Offs;
- if (!isLegalUse(NewF.AM, LU.MinOffset, LU.MaxOffset,
- LU.Kind, LU.AccessTy, TLI))
+ NewF.BaseOffset = Offset;
+ if (!isLegalUse(TTI, LU.MinOffset, LU.MaxOffset, LU.Kind, LU.AccessTy,
+ NewF))
continue;
NewF.ScaledReg = SE.getAddExpr(NegImmS, NewF.ScaledReg);
// immediate itself, then the formula isn't worthwhile.
if (const SCEVConstant *C = dyn_cast<SCEVConstant>(NewF.ScaledReg))
if (C->getValue()->isNegative() !=
- (NewF.AM.BaseOffs < 0) &&
- (C->getValue()->getValue().abs() * APInt(BitWidth, F.AM.Scale))
- .ule(abs64(NewF.AM.BaseOffs)))
+ (NewF.BaseOffset < 0) &&
+ (C->getValue()->getValue().abs() * APInt(BitWidth, F.Scale))
+ .ule(abs64(NewF.BaseOffset)))
continue;
// OK, looks good.
+ NewF.Canonicalize();
(void)InsertFormula(LU, LUIdx, NewF);
} else {
// Use the immediate in a base register.
if (BaseReg != OrigReg)
continue;
Formula NewF = F;
- NewF.AM.BaseOffs = (uint64_t)NewF.AM.BaseOffs + Imm;
- if (!isLegalUse(NewF.AM, LU.MinOffset, LU.MaxOffset,
- LU.Kind, LU.AccessTy, TLI)) {
- if (!TLI ||
- !TLI->isLegalAddImmediate((uint64_t)NewF.UnfoldedOffset + Imm))
+ NewF.BaseOffset = (uint64_t)NewF.BaseOffset + Imm;
+ if (!isLegalUse(TTI, LU.MinOffset, LU.MaxOffset,
+ LU.Kind, LU.AccessTy, NewF)) {
+ if (!TTI.isLegalAddImmediate((uint64_t)NewF.UnfoldedOffset + Imm))
continue;
NewF = F;
NewF.UnfoldedOffset = (uint64_t)NewF.UnfoldedOffset + Imm;
J = NewF.BaseRegs.begin(), JE = NewF.BaseRegs.end();
J != JE; ++J)
if (const SCEVConstant *C = dyn_cast<SCEVConstant>(*J))
- if ((C->getValue()->getValue() + NewF.AM.BaseOffs).abs().slt(
- abs64(NewF.AM.BaseOffs)) &&
+ if ((C->getValue()->getValue() + NewF.BaseOffset).abs().slt(
+ abs64(NewF.BaseOffset)) &&
(C->getValue()->getValue() +
- NewF.AM.BaseOffs).countTrailingZeros() >=
- CountTrailingZeros_64(NewF.AM.BaseOffs))
+ NewF.BaseOffset).countTrailingZeros() >=
+ countTrailingZeros<uint64_t>(NewF.BaseOffset))
goto skip_formula;
// Ok, looks good.
+ NewF.Canonicalize();
(void)InsertFormula(LU, LUIdx, NewF);
break;
skip_formula:;
// Collect the best formula for each unique set of shared registers. This
// is reset for each use.
- typedef DenseMap<SmallVector<const SCEV *, 2>, size_t, UniquifierDenseMapInfo>
+ typedef DenseMap<SmallVector<const SCEV *, 4>, size_t, UniquifierDenseMapInfo>
BestFormulaeTy;
BestFormulaeTy BestFormulae;
// the corresponding bad register from the Regs set.
Cost CostF;
Regs.clear();
- CostF.RateFormula(F, Regs, VisitedRegs, L, LU.Offsets, SE, DT,
+ CostF.RateFormula(TTI, F, Regs, VisitedRegs, L, LU.Offsets, SE, DT, LU,
&LoserRegs);
if (CostF.isLoser()) {
// During initial formula generation, undesirable formulae are generated
dbgs() << "\n");
}
else {
- SmallVector<const SCEV *, 2> Key;
+ SmallVector<const SCEV *, 4> Key;
for (SmallVectorImpl<const SCEV *>::const_iterator J = F.BaseRegs.begin(),
JE = F.BaseRegs.end(); J != JE; ++J) {
const SCEV *Reg = *J;
Cost CostBest;
Regs.clear();
- CostBest.RateFormula(Best, Regs, VisitedRegs, L, LU.Offsets, SE, DT);
+ CostBest.RateFormula(TTI, Best, Regs, VisitedRegs, L, LU.Offsets, SE,
+ DT, LU);
if (CostF < CostBest)
std::swap(F, Best);
DEBUG(dbgs() << " Filtering out formula "; F.print(dbgs());
I = F.BaseRegs.begin(), E = F.BaseRegs.end(); I != E; ++I) {
if (const SCEVConstant *C = dyn_cast<SCEVConstant>(*I)) {
Formula NewF = F;
- NewF.AM.BaseOffs += C->getValue()->getSExtValue();
+ NewF.BaseOffset += C->getValue()->getSExtValue();
NewF.BaseRegs.erase(NewF.BaseRegs.begin() +
(I - F.BaseRegs.begin()));
if (LU.HasFormulaWithSameRegs(NewF)) {
}
} else if (const SCEVUnknown *U = dyn_cast<SCEVUnknown>(*I)) {
if (GlobalValue *GV = dyn_cast<GlobalValue>(U->getValue()))
- if (!F.AM.BaseGV) {
+ if (!F.BaseGV) {
Formula NewF = F;
- NewF.AM.BaseGV = GV;
+ NewF.BaseGV = GV;
NewF.BaseRegs.erase(NewF.BaseRegs.begin() +
(I - F.BaseRegs.begin()));
if (LU.HasFormulaWithSameRegs(NewF)) {
/// for expressions like A, A+1, A+2, etc., allocate a single register for
/// them.
void LSRInstance::NarrowSearchSpaceByCollapsingUnrolledCode() {
- if (EstimateSearchSpaceComplexity() >= ComplexityLimit) {
- DEBUG(dbgs() << "The search space is too complex.\n");
+ if (EstimateSearchSpaceComplexity() < ComplexityLimit)
+ return;
- DEBUG(dbgs() << "Narrowing the search space by assuming that uses "
- "separated by a constant offset will use the same "
- "registers.\n");
+ DEBUG(dbgs() << "The search space is too complex.\n"
+ "Narrowing the search space by assuming that uses separated "
+ "by a constant offset will use the same registers.\n");
- // This is especially useful for unrolled loops.
+ // This is especially useful for unrolled loops.
- for (size_t LUIdx = 0, NumUses = Uses.size(); LUIdx != NumUses; ++LUIdx) {
- LSRUse &LU = Uses[LUIdx];
- for (SmallVectorImpl<Formula>::const_iterator I = LU.Formulae.begin(),
- E = LU.Formulae.end(); I != E; ++I) {
- const Formula &F = *I;
- if (F.AM.BaseOffs != 0 && F.AM.Scale == 0) {
- if (LSRUse *LUThatHas = FindUseWithSimilarFormula(F, LU)) {
- if (reconcileNewOffset(*LUThatHas, F.AM.BaseOffs,
- /*HasBaseReg=*/false,
- LU.Kind, LU.AccessTy)) {
- DEBUG(dbgs() << " Deleting use "; LU.print(dbgs());
- dbgs() << '\n');
-
- LUThatHas->AllFixupsOutsideLoop &= LU.AllFixupsOutsideLoop;
-
- // Update the relocs to reference the new use.
- for (SmallVectorImpl<LSRFixup>::iterator I = Fixups.begin(),
- E = Fixups.end(); I != E; ++I) {
- LSRFixup &Fixup = *I;
- if (Fixup.LUIdx == LUIdx) {
- Fixup.LUIdx = LUThatHas - &Uses.front();
- Fixup.Offset += F.AM.BaseOffs;
- // Add the new offset to LUThatHas' offset list.
- if (LUThatHas->Offsets.back() != Fixup.Offset) {
- LUThatHas->Offsets.push_back(Fixup.Offset);
- if (Fixup.Offset > LUThatHas->MaxOffset)
- LUThatHas->MaxOffset = Fixup.Offset;
- if (Fixup.Offset < LUThatHas->MinOffset)
- LUThatHas->MinOffset = Fixup.Offset;
- }
- DEBUG(dbgs() << "New fixup has offset "
- << Fixup.Offset << '\n');
- }
- if (Fixup.LUIdx == NumUses-1)
- Fixup.LUIdx = LUIdx;
- }
+ for (size_t LUIdx = 0, NumUses = Uses.size(); LUIdx != NumUses; ++LUIdx) {
+ LSRUse &LU = Uses[LUIdx];
+ for (SmallVectorImpl<Formula>::const_iterator I = LU.Formulae.begin(),
+ E = LU.Formulae.end(); I != E; ++I) {
+ const Formula &F = *I;
+ if (F.BaseOffset == 0 || (F.Scale != 0 && F.Scale != 1))
+ continue;
- // Delete formulae from the new use which are no longer legal.
- bool Any = false;
- for (size_t i = 0, e = LUThatHas->Formulae.size(); i != e; ++i) {
- Formula &F = LUThatHas->Formulae[i];
- if (!isLegalUse(F.AM,
- LUThatHas->MinOffset, LUThatHas->MaxOffset,
- LUThatHas->Kind, LUThatHas->AccessTy, TLI)) {
- DEBUG(dbgs() << " Deleting "; F.print(dbgs());
- dbgs() << '\n');
- LUThatHas->DeleteFormula(F);
- --i;
- --e;
- Any = true;
- }
- }
- if (Any)
- LUThatHas->RecomputeRegs(LUThatHas - &Uses.front(), RegUses);
+ LSRUse *LUThatHas = FindUseWithSimilarFormula(F, LU);
+ if (!LUThatHas)
+ continue;
- // Delete the old use.
- DeleteUse(LU, LUIdx);
- --LUIdx;
- --NumUses;
- break;
- }
+ if (!reconcileNewOffset(*LUThatHas, F.BaseOffset, /*HasBaseReg=*/ false,
+ LU.Kind, LU.AccessTy))
+ continue;
+
+ DEBUG(dbgs() << " Deleting use "; LU.print(dbgs()); dbgs() << '\n');
+
+ LUThatHas->AllFixupsOutsideLoop &= LU.AllFixupsOutsideLoop;
+
+ // Update the relocs to reference the new use.
+ for (SmallVectorImpl<LSRFixup>::iterator I = Fixups.begin(),
+ E = Fixups.end(); I != E; ++I) {
+ LSRFixup &Fixup = *I;
+ if (Fixup.LUIdx == LUIdx) {
+ Fixup.LUIdx = LUThatHas - &Uses.front();
+ Fixup.Offset += F.BaseOffset;
+ // Add the new offset to LUThatHas' offset list.
+ if (LUThatHas->Offsets.back() != Fixup.Offset) {
+ LUThatHas->Offsets.push_back(Fixup.Offset);
+ if (Fixup.Offset > LUThatHas->MaxOffset)
+ LUThatHas->MaxOffset = Fixup.Offset;
+ if (Fixup.Offset < LUThatHas->MinOffset)
+ LUThatHas->MinOffset = Fixup.Offset;
}
+ DEBUG(dbgs() << "New fixup has offset " << Fixup.Offset << '\n');
}
+ if (Fixup.LUIdx == NumUses-1)
+ Fixup.LUIdx = LUIdx;
}
- }
- DEBUG(dbgs() << "After pre-selection:\n";
- print_uses(dbgs()));
+ // Delete formulae from the new use which are no longer legal.
+ bool Any = false;
+ for (size_t i = 0, e = LUThatHas->Formulae.size(); i != e; ++i) {
+ Formula &F = LUThatHas->Formulae[i];
+ if (!isLegalUse(TTI, LUThatHas->MinOffset, LUThatHas->MaxOffset,
+ LUThatHas->Kind, LUThatHas->AccessTy, F)) {
+ DEBUG(dbgs() << " Deleting "; F.print(dbgs());
+ dbgs() << '\n');
+ LUThatHas->DeleteFormula(F);
+ --i;
+ --e;
+ Any = true;
+ }
+ }
+
+ if (Any)
+ LUThatHas->RecomputeRegs(LUThatHas - &Uses.front(), RegUses);
+
+ // Delete the old use.
+ DeleteUse(LU, LUIdx);
+ --LUIdx;
+ --NumUses;
+ break;
+ }
}
+
+ DEBUG(dbgs() << "After pre-selection:\n"; print_uses(dbgs()));
}
/// NarrowSearchSpaceByRefilteringUndesirableDedicatedRegisters - Call
// Pick the register which is used by the most LSRUses, which is likely
// to be a good reuse register candidate.
- const SCEV *Best = 0;
+ const SCEV *Best = nullptr;
unsigned BestNum = 0;
for (RegUseTracker::const_iterator I = RegUses.begin(), E = RegUses.end();
I != E; ++I) {
// reference that register in order to be considered. This prunes out
// unprofitable searching.
SmallSetVector<const SCEV *, 4> ReqRegs;
- for (SmallPtrSet<const SCEV *, 16>::const_iterator I = CurRegs.begin(),
- E = CurRegs.end(); I != E; ++I)
- if (LU.Regs.count(*I))
- ReqRegs.insert(*I);
+ for (const SCEV *S : CurRegs)
+ if (LU.Regs.count(S))
+ ReqRegs.insert(S);
SmallPtrSet<const SCEV *, 16> NewRegs;
Cost NewCost;
E = LU.Formulae.end(); I != E; ++I) {
const Formula &F = *I;
- // Ignore formulae which do not use any of the required registers.
- bool SatisfiedReqReg = true;
+ // Ignore formulae which may not be ideal in terms of register reuse of
+ // ReqRegs. The formula should use all required registers before
+ // introducing new ones.
+ int NumReqRegsToFind = std::min(F.getNumRegs(), ReqRegs.size());
for (SmallSetVector<const SCEV *, 4>::const_iterator J = ReqRegs.begin(),
JE = ReqRegs.end(); J != JE; ++J) {
const SCEV *Reg = *J;
- if ((!F.ScaledReg || F.ScaledReg != Reg) &&
- std::find(F.BaseRegs.begin(), F.BaseRegs.end(), Reg) ==
+ if ((F.ScaledReg && F.ScaledReg == Reg) ||
+ std::find(F.BaseRegs.begin(), F.BaseRegs.end(), Reg) !=
F.BaseRegs.end()) {
- SatisfiedReqReg = false;
- break;
+ --NumReqRegsToFind;
+ if (NumReqRegsToFind == 0)
+ break;
}
}
- if (!SatisfiedReqReg) {
+ if (NumReqRegsToFind != 0) {
// If none of the formulae satisfied the required registers, then we could
// clear ReqRegs and try again. Currently, we simply give up in this case.
continue;
// the current best, prune the search at that point.
NewCost = CurCost;
NewRegs = CurRegs;
- NewCost.RateFormula(F, NewRegs, VisitedRegs, L, LU.Offsets, SE, DT);
+ NewCost.RateFormula(TTI, F, NewRegs, VisitedRegs, L, LU.Offsets, SE, DT,
+ LU);
if (NewCost < SolutionCost) {
Workspace.push_back(&F);
if (Workspace.size() != Uses.size()) {
} else {
DEBUG(dbgs() << "New best at "; NewCost.print(dbgs());
dbgs() << ".\n Regs:";
- for (SmallPtrSet<const SCEV *, 16>::const_iterator
- I = NewRegs.begin(), E = NewRegs.end(); I != E; ++I)
- dbgs() << ' ' << **I;
+ for (const SCEV *S : NewRegs)
+ dbgs() << ' ' << *S;
dbgs() << '\n');
SolutionCost = NewCost;
void LSRInstance::Solve(SmallVectorImpl<const Formula *> &Solution) const {
SmallVector<const Formula *, 8> Workspace;
Cost SolutionCost;
- SolutionCost.Loose();
+ SolutionCost.Lose();
Cost CurCost;
SmallPtrSet<const SCEV *, 16> CurRegs;
DenseSet<const SCEV *> VisitedRegs;
}
bool AllDominate = true;
- Instruction *BetterPos = 0;
+ Instruction *BetterPos = nullptr;
Instruction *Tentative = IDom->getTerminator();
for (SmallVectorImpl<Instruction *>::const_iterator I = Inputs.begin(),
E = Inputs.end(); I != E; ++I) {
// instead of at the end, so that it can be used for other expansions.
if (IDom == Inst->getParent() &&
(!BetterPos || !DT.dominates(Inst, BetterPos)))
- BetterPos = llvm::next(BasicBlock::iterator(Inst));
+ BetterPos = std::next(BasicBlock::iterator(Inst));
}
if (!AllDominate)
break;
SCEVExpander &Rewriter,
SmallVectorImpl<WeakVH> &DeadInsts) const {
const LSRUse &LU = Uses[LF.LUIdx];
+ if (LU.RigidFormula)
+ return LF.OperandValToReplace;
// Determine an input position which will be dominated by the operands and
// which will dominate the result.
LF.UserInst, LF.OperandValToReplace,
Loops, SE, DT);
- Ops.push_back(SE.getUnknown(Rewriter.expandCodeFor(Reg, 0, IP)));
+ Ops.push_back(SE.getUnknown(Rewriter.expandCodeFor(Reg, nullptr, IP)));
}
// Expand the ScaledReg portion.
- Value *ICmpScaledV = 0;
- if (F.AM.Scale != 0) {
+ Value *ICmpScaledV = nullptr;
+ if (F.Scale != 0) {
const SCEV *ScaledS = F.ScaledReg;
// If we're expanding for a post-inc user, make the post-inc adjustment.
Loops, SE, DT);
if (LU.Kind == LSRUse::ICmpZero) {
- // An interesting way of "folding" with an icmp is to use a negated
- // scale, which we'll implement by inserting it into the other operand
- // of the icmp.
- assert(F.AM.Scale == -1 &&
- "The only scale supported by ICmpZero uses is -1!");
- ICmpScaledV = Rewriter.expandCodeFor(ScaledS, 0, IP);
+ // Expand ScaleReg as if it was part of the base regs.
+ if (F.Scale == 1)
+ Ops.push_back(
+ SE.getUnknown(Rewriter.expandCodeFor(ScaledS, nullptr, IP)));
+ else {
+ // An interesting way of "folding" with an icmp is to use a negated
+ // scale, which we'll implement by inserting it into the other operand
+ // of the icmp.
+ assert(F.Scale == -1 &&
+ "The only scale supported by ICmpZero uses is -1!");
+ ICmpScaledV = Rewriter.expandCodeFor(ScaledS, nullptr, IP);
+ }
} else {
// Otherwise just expand the scaled register and an explicit scale,
// which is expected to be matched as part of the address.
// Flush the operand list to suppress SCEVExpander hoisting address modes.
- if (!Ops.empty() && LU.Kind == LSRUse::Address) {
+ // Unless the addressing mode will not be folded.
+ if (!Ops.empty() && LU.Kind == LSRUse::Address &&
+ isAMCompletelyFolded(TTI, LU, F)) {
Value *FullV = Rewriter.expandCodeFor(SE.getAddExpr(Ops), Ty, IP);
Ops.clear();
Ops.push_back(SE.getUnknown(FullV));
}
- ScaledS = SE.getUnknown(Rewriter.expandCodeFor(ScaledS, 0, IP));
- ScaledS = SE.getMulExpr(ScaledS,
- SE.getConstant(ScaledS->getType(), F.AM.Scale));
+ ScaledS = SE.getUnknown(Rewriter.expandCodeFor(ScaledS, nullptr, IP));
+ if (F.Scale != 1)
+ ScaledS =
+ SE.getMulExpr(ScaledS, SE.getConstant(ScaledS->getType(), F.Scale));
Ops.push_back(ScaledS);
}
}
// Expand the GV portion.
- if (F.AM.BaseGV) {
+ if (F.BaseGV) {
// Flush the operand list to suppress SCEVExpander hoisting.
if (!Ops.empty()) {
Value *FullV = Rewriter.expandCodeFor(SE.getAddExpr(Ops), Ty, IP);
Ops.clear();
Ops.push_back(SE.getUnknown(FullV));
}
- Ops.push_back(SE.getUnknown(F.AM.BaseGV));
+ Ops.push_back(SE.getUnknown(F.BaseGV));
}
// Flush the operand list to suppress SCEVExpander hoisting of both folded and
}
// Expand the immediate portion.
- int64_t Offset = (uint64_t)F.AM.BaseOffs + LF.Offset;
+ int64_t Offset = (uint64_t)F.BaseOffset + LF.Offset;
if (Offset != 0) {
if (LU.Kind == LSRUse::ICmpZero) {
// The other interesting way of "folding" with an ICmpZero is to use a
if (LU.Kind == LSRUse::ICmpZero) {
ICmpInst *CI = cast<ICmpInst>(LF.UserInst);
DeadInsts.push_back(CI->getOperand(1));
- assert(!F.AM.BaseGV && "ICmp does not support folding a global value and "
+ assert(!F.BaseGV && "ICmp does not support folding a global value and "
"a scale at the same time!");
- if (F.AM.Scale == -1) {
+ if (F.Scale == -1) {
if (ICmpScaledV->getType() != OpTy) {
Instruction *Cast =
CastInst::Create(CastInst::getCastOpcode(ICmpScaledV, false,
}
CI->setOperand(1, ICmpScaledV);
} else {
- assert(F.AM.Scale == 0 &&
+ // A scale of 1 means that the scale has been expanded as part of the
+ // base regs.
+ assert((F.Scale == 0 || F.Scale == 1) &&
"ICmp does not support folding a global value and "
"a scale at the same time!");
Constant *C = ConstantInt::getSigned(SE.getEffectiveSCEVType(OpTy),
Loop *PNLoop = LI.getLoopFor(Parent);
if (!PNLoop || Parent != PNLoop->getHeader()) {
// Split the critical edge.
- BasicBlock *NewBB = 0;
+ BasicBlock *NewBB = nullptr;
if (!Parent->isLandingPad()) {
NewBB = SplitCriticalEdge(BB, Parent, P,
/*MergeIdenticalEdges=*/true,
SplitLandingPadPredecessors(Parent, BB, "", "", P, NewBBs);
NewBB = NewBBs[0];
}
-
- // If PN is outside of the loop and BB is in the loop, we want to
- // move the block to be immediately before the PHI block, not
- // immediately after BB.
- if (L->contains(BB) && !L->contains(PN))
- NewBB->moveBefore(PN->getParent());
-
- // Splitting the edge can reduce the number of PHI entries we have.
- e = PN->getNumIncomingValues();
- BB = NewBB;
- i = PN->getBasicBlockIndex(BB);
+ // If NewBB==NULL, then SplitCriticalEdge refused to split because all
+ // phi predecessors are identical. The simple thing to do is skip
+ // splitting in this case rather than complicate the API.
+ if (NewBB) {
+ // If PN is outside of the loop and BB is in the loop, we want to
+ // move the block to be immediately before the PHI block, not
+ // immediately after BB.
+ if (L->contains(BB) && !L->contains(PN))
+ NewBB->moveBefore(PN->getParent());
+
+ // Splitting the edge can reduce the number of PHI entries we have.
+ e = PN->getNumIncomingValues();
+ BB = NewBB;
+ i = PN->getBasicBlockIndex(BB);
+ }
}
}
std::pair<DenseMap<BasicBlock *, Value *>::iterator, bool> Pair =
- Inserted.insert(std::make_pair(BB, static_cast<Value *>(0)));
+ Inserted.insert(std::make_pair(BB, static_cast<Value *>(nullptr)));
if (!Pair.second)
PN->setIncomingValue(i, Pair.first->second);
else {
Changed |= DeleteTriviallyDeadInstructions(DeadInsts);
}
-LSRInstance::LSRInstance(const TargetLowering *tli, Loop *l, Pass *P)
- : IU(P->getAnalysis<IVUsers>()),
- SE(P->getAnalysis<ScalarEvolution>()),
- DT(P->getAnalysis<DominatorTree>()),
- LI(P->getAnalysis<LoopInfo>()),
- TLI(tli), L(l), Changed(false), IVIncInsertPos(0) {
-
+LSRInstance::LSRInstance(Loop *L, Pass *P)
+ : IU(P->getAnalysis<IVUsers>()), SE(P->getAnalysis<ScalarEvolution>()),
+ DT(P->getAnalysis<DominatorTreeWrapperPass>().getDomTree()),
+ LI(P->getAnalysis<LoopInfo>()),
+ TTI(P->getAnalysis<TargetTransformInfo>()), L(L), Changed(false),
+ IVIncInsertPos(nullptr) {
// If LoopSimplify form is not available, stay out of trouble.
if (!L->isLoopSimplifyForm())
return;
#endif // DEBUG
DEBUG(dbgs() << "\nLSR on loop ";
- WriteAsOperand(dbgs(), L->getHeader(), /*PrintType=*/false);
+ L->getHeader()->printAsOperand(dbgs(), /*PrintType=*/false);
dbgs() << ":\n");
// First, perform some low-level loop optimizations.
#ifndef NDEBUG
// Formulae should be legal.
- for (SmallVectorImpl<LSRUse>::const_iterator I = Uses.begin(),
- E = Uses.end(); I != E; ++I) {
- const LSRUse &LU = *I;
- for (SmallVectorImpl<Formula>::const_iterator J = LU.Formulae.begin(),
- JE = LU.Formulae.end(); J != JE; ++J)
- assert(isLegalUse(J->AM, LU.MinOffset, LU.MaxOffset,
- LU.Kind, LU.AccessTy, TLI) &&
- "Illegal formula generated!");
+ for (SmallVectorImpl<LSRUse>::const_iterator I = Uses.begin(), E = Uses.end();
+ I != E; ++I) {
+ const LSRUse &LU = *I;
+ for (SmallVectorImpl<Formula>::const_iterator J = LU.Formulae.begin(),
+ JE = LU.Formulae.end();
+ J != JE; ++J)
+ assert(isLegalUse(TTI, LU.MinOffset, LU.MaxOffset, LU.Kind, LU.AccessTy,
+ *J) && "Illegal formula generated!");
};
#endif
print_uses(OS);
}
+#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
void LSRInstance::dump() const {
print(errs()); errs() << '\n';
}
+#endif
namespace {
class LoopStrengthReduce : public LoopPass {
- /// TLI - Keep a pointer of a TargetLowering to consult for determining
- /// transformation profitability.
- const TargetLowering *const TLI;
-
public:
static char ID; // Pass ID, replacement for typeid
- explicit LoopStrengthReduce(const TargetLowering *tli = 0);
+ LoopStrengthReduce();
private:
- bool runOnLoop(Loop *L, LPPassManager &LPM);
- void getAnalysisUsage(AnalysisUsage &AU) const;
+ bool runOnLoop(Loop *L, LPPassManager &LPM) override;
+ void getAnalysisUsage(AnalysisUsage &AU) const override;
};
}
char LoopStrengthReduce::ID = 0;
INITIALIZE_PASS_BEGIN(LoopStrengthReduce, "loop-reduce",
"Loop Strength Reduction", false, false)
-INITIALIZE_PASS_DEPENDENCY(DominatorTree)
+INITIALIZE_AG_DEPENDENCY(TargetTransformInfo)
+INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
INITIALIZE_PASS_DEPENDENCY(ScalarEvolution)
INITIALIZE_PASS_DEPENDENCY(IVUsers)
INITIALIZE_PASS_DEPENDENCY(LoopInfo)
"Loop Strength Reduction", false, false)
-Pass *llvm::createLoopStrengthReducePass(const TargetLowering *TLI) {
- return new LoopStrengthReduce(TLI);
+Pass *llvm::createLoopStrengthReducePass() {
+ return new LoopStrengthReduce();
}
-LoopStrengthReduce::LoopStrengthReduce(const TargetLowering *tli)
- : LoopPass(ID), TLI(tli) {
- initializeLoopStrengthReducePass(*PassRegistry::getPassRegistry());
- }
+LoopStrengthReduce::LoopStrengthReduce() : LoopPass(ID) {
+ initializeLoopStrengthReducePass(*PassRegistry::getPassRegistry());
+}
void LoopStrengthReduce::getAnalysisUsage(AnalysisUsage &AU) const {
// We split critical edges, so we change the CFG. However, we do update
AU.addRequired<LoopInfo>();
AU.addPreserved<LoopInfo>();
AU.addRequiredID(LoopSimplifyID);
- AU.addRequired<DominatorTree>();
- AU.addPreserved<DominatorTree>();
+ AU.addRequired<DominatorTreeWrapperPass>();
+ AU.addPreserved<DominatorTreeWrapperPass>();
AU.addRequired<ScalarEvolution>();
AU.addPreserved<ScalarEvolution>();
// Requiring LoopSimplify a second time here prevents IVUsers from running
AU.addRequiredID(LoopSimplifyID);
AU.addRequired<IVUsers>();
AU.addPreserved<IVUsers>();
+ AU.addRequired<TargetTransformInfo>();
}
bool LoopStrengthReduce::runOnLoop(Loop *L, LPPassManager & /*LPM*/) {
+ if (skipOptnoneFunction(L))
+ return false;
+
bool Changed = false;
// Run the main LSR transformation.
- Changed |= LSRInstance(TLI, L, this).getChanged();
+ Changed |= LSRInstance(L, this).getChanged();
// Remove any extra phis created by processing inner loops.
Changed |= DeleteDeadPHIs(L->getHeader());
- if (EnablePhiElim) {
+ if (EnablePhiElim && L->isLoopSimplifyForm()) {
SmallVector<WeakVH, 16> DeadInsts;
SCEVExpander Rewriter(getAnalysis<ScalarEvolution>(), "lsr");
#ifndef NDEBUG
Rewriter.setDebugType(DEBUG_TYPE);
#endif
- unsigned numFolded = Rewriter.
- replaceCongruentIVs(L, &getAnalysis<DominatorTree>(), DeadInsts, TLI);
+ unsigned numFolded = Rewriter.replaceCongruentIVs(
+ L, &getAnalysis<DominatorTreeWrapperPass>().getDomTree(), DeadInsts,
+ &getAnalysis<TargetTransformInfo>());
if (numFolded) {
Changed = true;
DeleteTriviallyDeadInstructions(DeadInsts);
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